So, for most Apple products, absolutely not. Not for iPhone, iPad, and definitely not for Apple Series 6/7/8 watches. I treat my iPhone, iPad and Apple Watch like garbage and I've never, ever had a screen scratch. iPhone has been dropped, thrown, flipped -- no damage. My Apple Series 7 has been banged into all kinds of stuff -- not a mark on the screen. I clean them with alchohol or glass cleaner and paper towels -- I don't even care, I'll put any damn cleaner on iPhone/iPad/Apple Watch and I've never, ever had a problem or scratched screen in fifteen years.
But, the Series 7 / 8 and the new Ultra have sapphire crystals -- it's the same glass you'd find on a Rolex or other high-end watches. Sapphire crystal has excellent scratch resistance, it's only a small step down from diamond.
The CE comes with Ion-X glass. I've no experience with it, but it's going to be softer than sapphire crystal. Personally, I would not use a film or protector. I hate the damn things with a passion, they are a massive waste of money. But just be aware, a Series 8 or Ultra is going to have better front glass. Still think the CE is a great deal though.