Earlier quoted context omitted.
Having run a mail server, I don't think it's reasonable to expect most people to contain the deluge of spam and phishing attacks they would get if just told them to "sort it out" themselves.
You misunderstood. Don’t require users to build their bubbles, but have providers offer bubbles for a user to choose from. You could even have external bubble providers that offer different technologies and qualities of filters. Just don’t have one centralised overlord.
Sign up for Twitter. Immediately you're greeted with a list of "suggested filters" that will pop up again and again, using dark patterns eventually, until you either give in or are tricked into adding Twitter's highly recommended "safe filter plus package" that uses the exact same shadow bans and biased algorithms used by default today.