Everyone describes the fediverse as similar to email. What would happen if Yahoo refused to send emails through to Gmail because they are too big? Does everyone need ten emails?
Some people feel more comfortable on small instances where they feel seen. Some feel more comfortable on a large instance where they blend into a crowd. Let's focus on moderation as the issue and not make people feel guilty for choosing a large instance if it's where they feel most comfortable.
@blithe @rysiek It's not unknown for GMail to block mail from known spammer IP addresses, so I'm not sure what your point is.