I’m not using any screen protector on my new phone (not yet anyway). I don’t think it’s an issue with screen sensitivity. How I see it, the issue is that in order to advance the screen left or right (say in an image carousel), I have to stretch my thumb really far over to the left side of the screen. If I don’t reach really far over, and just do a lazy right flick instead, the screen registers the touch and moves right a little bit, but when I lift my thumb, the current screen just springs back into place instead of advancing to the next screen. It’s most noticeable when viewing screenshots in the app store.
I think you’re on to something w/ transition scale or animation scale, even though I’m not seeing them in GrapheneOS settings even after activating developer mode. I may just need to request this feature in GrapheneOS or look for a third party app that unlocks this setting. You’ve also given me a new phrase to search for, so thank you for that.
EDIT: I found Transition Scale and Animation Scale in GrapheneOS after activating developer mode, not sure what I did differently this time. Alas, neither of those settings solves the problem, so the hunt continues.