In a way I can agree to that, because in the Windows ecosystem so many things are opaque to an extent, that the ability to make informed technical decisions is severely limited, i.e. factually crippled: One has to fill the huge gaps of information (from the perspective of an OSS developer) with guesswork. Ultimately the Windows ecosystem forces one to live with oversimplifications, because more comprehensive information is not publicly available. This is why I ceased to use it decades ago.
The simple answer (at least at the start) is very useful IF it can encourage someone to start at all,
IMO that is manipulating people: Depicting something in a way, that the “right” decision seems to be obvious, because that is how you want them to decide. Side note, not fully serious: As you also perceive that as doing something good for people, becoming a politician might be a perfect fit. 
Apart from that, I do neither believe that the “target group” for such deliberately oversimplified statements is helpful for SailfishOS in its current state nor that SailfishOS is helpful for technically clueless people.
My “simple guidance” when discussing SailfishOS (and even that is with IT people most of the time):
- If you are afraid of having to use the command line every now and then, SailfishOS will not suit you.
- If you are not willing to invest some time to get familiar with the peculiarities of SailfishOS, you will have a limited SailfishOS experience. The amount of time required mostly and heavily depends on the Linux skills one has. But one can also acquire Linux skills with SailfishOS as with any other Linux distribution.
- You will not have the full functionalities and as simple UI-based workflows with a SailfishOS device as with a modern Android or iOS device. But on some supported devices the essential functionalities are basicially all there: Of the “officially supported” devices that is currently the Xperias 10 III & II, and it looks like the Xperias 10 V & IV might reach that state this year.
After reading how you depict the “target group” you have in mind, I think I should add:
- If aforementioned points comprise too much information for you, SailfishOS is definitely not for you.
The bitter truth is even grimmer, and these points I usually do not actively address (i.e. only when asked):
- Actually, you become a UNIX system-administrator when using SailfishOS, as with any other Linux distribution, like it or not.
- While owning a mobile device one has full control over is apparently the aim of many SailfishOS users, “with great powers come great responsibilities”: You are the only one who is in control of this device (as with any other, more common Linux distribution), it is solely your responsibility to manage your SailfishOS device(s) properly.
I think this will never lead to anything useful because as always this is starting to be a struggle about winning an arguement …
Well, I don’t “struggle”, as I do not intend to “win an argument”.
But each time I replied, I thought when reading your message I then replied to: These are wrong answers to senseless questions; O.K. if you want to think so, but this is presented as guidance / advice for others in a public forum.
… rather then finding a common middle ground or a good solution to the starting problem.
Sorry, many things are not negotiable, e.g. there cannot be a “middle ground” between right and wrong (supposedly that ends up at such half-right/half-wrong assessments as the original one we discussed here; BTW, that was your own statement). But for vast areas of life simply “it is what it is” is true: Classical physics, chemistry, biology, maths etc. and their consequences are nothing to discuss (in contrast to current research in these fields). Among the “consequences” of natural sciences technical truths emerge, and other ugly things as e.g. the discovery of global warming; hence these things are also nothing to discuss, only to research to acquire knowledge (if one wants to).
What one can discuss are assessments of how to interpret these facts and which decisions one might make, based on these facts. But to deliberately start with oversimplifications to let people make the decisions you envision for them, is not the right track specifically and not a suitable scheme for human interactions in general, IMO.
Would you really prefer, if I apply that scheme to you? I.e. deliberately depicting things in a distorted, simplified manner to let my suggestions appear as inevitable. No, I don’t (i.e. I do not come up similarly simplified suggestions), instead I try hard to point out the complexities and pitfalls of oversimplifying technical aspects and (later) logic, patterns of thinking, lines of argumentation, etc.
Heck, the world, life, almost everything is quite complex (but complexity is not necessarily complicated to comprehend, usually it is structured, i.e. follows rules one may research, or not). Live with it! I strongly believe that oversimplifications are not the right tool for coping with that.
So I am going to be the adult here and end this: You are right, I am wrong in a technical sense.
Oh, but I did not claim to know any “right statement” you wanted to extract from me by questions crafted for that purpose; actually, I actively refused to make such a statement. I merely pointed out that neither you or me or anybody else outside of Jolla can meet an informed decision for your ordered list of Stores WRT “security”. And I denoted that first one has to ask what “security” means for someone in a specific scenario / use-case / set-up.
P.S.: BTW, the “simple answer” to the original question (without the concluding “if you are forced to oversimplify on software security”) is IMO:
Install all three Stores, you will most likely use all of them sooner and later. As a proper curation of submitted software cannot be expected, do read app descriptions and comments thoroughly and apply common sense, before you install something, and keep it that way (i.e. do not become negligent over time).
I originally considered to write something socially soothing as “well, your list might be suitable for suggesting in which order one should walk through the three Stores to look for an app (i.e. a specific functionality) and install it”. But then one would end up with a few deliberately crippled apps due to the Jolla Store rules, while OpenRepos and / or SailfishOS:Chum offer the fully intact variants of these apps.
You see, oversimplifications are often directly counterproductive in relevant aspects. It is complicated, and neither you or me can realistically change that, especially not by modelling or merely depicting it as simple.
BTW (just a thought I had, because I encountered that with people telling me such oversimplified stuff a few times):
- Aren’t you afraid that somebody following your oversimplified advice may run to into a pitfall which did not exist in your simplified presentation of the topic?
Or simply discover that there is much more to know?
Then that person may:
- Model you as clueless, because you did not indicate that there is more to know which might be relevant.
- Model you as manipulative, when the information reaches them that you deliberately oversimplify to make people following your suggestions.
- Or as a simpler model: Model you as evil because you did not warn them that you deliberately oversimplified, despite knowing better.
- Aren’t you afraid that you will start to believe your own, oversimplified assessments, and become less aware that there is much more to know / working under the hood / etc.?
And hence cease to research things to acquire knowledge?