If you want scratch protection then factory protector is ok.
But if you drop your phone and have a tempered glass on it, then some of that energy is absorbed by the tempered glass and possibly saving your screen.
The fingerprint sensor in the glass is the stupidest thing ever done because of the technology behind it.
The fingerprint sensor was perfect when it the back and no problems with tempered glass protection. Only logical explanation is Samsung wants your phone unprotected against drops.
I have used White tower to cheap ebay screens and few between... all of them do not last and expensive for no apperant reason besides some gimmick fingerprint sensor. Thanks Samsung for taking an amazing phone and making it crappy.
I removed the factory screen protector and used a Zagg screen protector, I pre-ordered so the Zagg was one of the only ones out there at the time but I've loved it I've been rough on my S10 and the Zagg has kept my screen safe and I've never had an issue with the fingerprint sensor