I ride everything from cross country type trails to downhill to full on jump parks. I do get a little sweat in between the glass on longer rides but I just take it off and wipe it down and all good. It’s a small price to pay for a scratch free watch.I did use full-screen add-on protectors in the past but proved very unusable for me. I do sweat quite a lot and the trapping of humidity in between screen and protector made all the on-screen manipulation impossible.
I also think, there is a difference between riding XC and ringing Enduro / All Mountain when it comes to vibration. What kind of riding do you pracice?