Maybe the bridge can reply (from its own account) if it detect a message was blocked? Then instead of thinking your Fediverse friend hates you, you can tell them (out of band) to evacuate.
Is there an easy way to tell which instances block vs which ones are just not very well synced? Or is it considered a feature to be intransparent about censorship?
I often can't find myself on other instances. Sometimes I follow someone but my replies seem to get blackholed / denyholed.
But here everything shows up smoothly: https://gleasonator.com/@8685ebef665338dd6931e2ccdf3c19d9f0e5a1067c918f22e7081c2558f8faf8@mostr.pub/posts/AYzmgHNMCYBNzGlvKS
Discussion
Also, do DM's actually make it accross the bridge? Obviously they'd lose e2e encryption. If not, again there should be some auto-reply from the bridge.