After wasting too much time looking into who's blocking who in the #fediverse it's clear that the #fediverse is objectively a failure as a communications platform - and that includes #gab. Why?

gab.com blocks mstdn.jp - mstdn.jp allows gab
mastodon.xyz blocks gab.com - gab.com does not block mastodon.xyz
mstdn.io doesn't block gab and gab doesn't block mstdn.io

What happens if you are using mstdn.jp you send a message to someone at gab? It gets shown as being "sent" - but it never gets through. The result is.. if you want to message someone on gab or some fediverse instance you'll have to sign up at that server to be sure the message gets through. You have no idea if it does or doesn't if you just send a message.

Imagine Microsoft Outlook and GMail and Protonmail decided to behave in a similar fashion. Outlook could send to GMail but not Protonmail, Protonmail could send Outlook but not receive replies.. there wouldn't be much use for e-mail at all if it worked like that.