That's a good point. Branding is done for a reason. When I buy a car, I don't need to know which companies made each and every component, it's enough for me to know that "Audi" made it.
I guess if someone made an easy entry-point for users to sign up, that became the defacto way to start with Lemmy, then it would have a lower barrier to entry. Maybe it asks them some likes/dislikes, and then it would route them to the most appropriate instance to sign up.