Is there a way - maybe even through the command line - to configure a higher touch sensitivity?
Since I added the “Panzerglas”-protector, the XA2 only recognizes exceptionally hard pushes. Some forums suggest that Android had a setting to increase sensitivity, so I figure the possibility might be there for Sailfish as well?
Screen protectors are unnecessary and as noted always makes the experience worse. Just don’t use them.
100% NOT TRUE !!! 
Just don’t buy a crappy one like some people apparently do because it was cheap…
Just one data point, but my Xperia 10 II has shared the same pocket as my keys for the past 8 months and the screen is still in perfect condition.