I wouldn't be worried about damaging the gun. I would think about possible theft and I would get a holster for it that was easy to put on and take off with the gun in the holster. A lot of accidents happen, especially with striker fired guns, when holstering or re holstering the gun. All it takes is clothes something to get caught in the trigger guard or hanging the trigger on an edge of the holster.

Reduces the life of your ammo. I tend to swap out carry ammo once a year or so just to be safe. If you live in a humid environment (aka the south) be sure you keep your gun clean and well lubricated so you don't get rust.

I prefer stainless for a carry gun because if the higher resistance to rust b/c of humidity and sweat. However, I have been carrying a blued gun lately. I may have the slide cerecoated to help prevent wear and rust.

Something else to consider is, if your carry piece has been in a very cold car all day, then you bring it inside, I'd set outside of the holster to prevent moisture from collecting.

As said above, make sure you regularly clean your gun and don't forget the magazines. Makes sure they are clean on the inside and your springs are in good shape. If you pocket carry a revolver, make sure to keep the pocket lint cleaned away from the hammer.

This is why I carry a Glock.

This is why I carry a Glock.

My gun is a Cobra with the tactical tan cerakote. The gun itself is alloy, so maybe rust won't be a problem. Anyway, I like to shoot, so old ammo won't be an issue. I don't plan to leave it in my car except during work, so maybe I won't have some of the other issues.