It's not too hard to understand. Some people just like to pretend it's complicated. It's literally the same system email uses, and almost everyone has figured out how to use that. There's no marketing for it though. It's only word-of-mouth, and let's be honest, us fediverse users often aren't the best at communicating simply.

It'd be smart if some fediverse instances provided an email account with your account. Then we can just tell people to create an email account and they'd accidentally have a fediverse account.