Another data point: I've been using my Gemini for hours every day since I got it nearly 5 years ago (May 2018 — doesn't time fly!), and although I removed the screen protector almost immediately, the screen is as good as new.
Yes, the screen does attract faint prints from the keys, but that's just traces of grease, and it all wipes off. I clean the screen every few days with a microfibre cloth (which has occasionally been sprayed with a cleaning solution), and all the greasy marks from touching the screen and from the keys vanish with no trace. So the keys don't have any permanent (chemical or physical) effect on the screen.
(Also, IIRC, while the Gemini is perfectly usable with the protector in place, without it the screen looks a fraction clearer, feels a fraction more positive, and responds a fraction better.)
So there's no real reason to use a protector, and you should feel free to remove it!