If you want to protect your privacy against viewers of your videos, how you upload them to YouTube makes more or less no difference. With this scenario the question is how much information are you leaking in your content, and that’d cover everything from writing style idiosyncracies to anything that can be used to potentially identify eg. where you live and so on.

If you’re worried about “malicious hackers”, then the question is who are these potential hackers you’re protecting against? Would they be attacking Google or you? If it’s you, then how you upload things to YT is again completely meaningless. If they’re attacking Google and get far enough to actually exfil data, what they’d actually be able to get out of it is anybody’s guess. Using a VPN and a throwaway email is probably good enough in any case.