I know a lot of folks say it’s not necessary but I scratched the hell out of my first two AWs. So much so that it was cheaper to replace the watch than repair it. Life of a plumber, I guess. Don’t really care for the big, bulky snap on ones. Have tried a lot of the little glass ones you put over the screen, they’re nice but hell it takes me 10 minutes to input the code to open the thing in the morning. Scrolling through the apps is a nightmare.
You aren’t going to scratch the ultra. There isn’t much out there that will scratch the sapphire crystal.
Did you have originally the standard aluminum Apple Watch? If so, that’s why. The base aluminum Apple Watch uses standard gorilla glass. The stainless steel, and up versions (including titanium and ultra), use sapphire glass. You’re not gonna be able to scratch it at all. I remember when I bought my first Apple Watch series 2, I went for the aluminum. Scratched it like crazy so easily. Ever since then I’ve gone stainless steel, and I’ve never scratched them in years of use.