To avoid Android having access to your data:
Create a secondary user and put all your data there.
Only switch to the primary user for Android apps.
Until now, I didn’t notice the presence of my data in the few Android apps I use.
Caveat: backup often. Data can be lost.
The cause is probably if you start/stop Android Support and switch user too fast.
But
I happened only twice to me and not since a long time. I enabled debug symbols on home partition. Not sure it is related but no problems since that.
Warning: Don’t forget to stop Android before switching user or it will “see” everithing in your secondary user.
Using that trick everyday and happy.
Edit: To be 100% honest: I didn’t make deep research to be sure Android has no access to my data. I only noticed Android apps seeing empty gallery, empty contacts, etc
Also, a softer way to hide things to Android here.