Thought so too, but I can join LAN games perfectly fine. And other titles that have multiplayer over LAN function properly on it.
This is still occurring for many people even today, so I don't consider this resolved, especially since it's likely a certain update that caused it. It didn't happen to me personally but it did to someone I know. Earlier today it was fine, then we closed the game, reopened it, and boom some content disappeared and also got the "failed to load character 3" error. Will be contacting Mojang support, however.
https://bugs.mojang.com/browse/MCCE-10700
https://www.reddit.com/r/Minecraft/comments/d2g4tf/bedrock_lost_all_my_purchases/
And ironically the issue does not appear to be present in the 1.17.20.22 BETA. So will likely be fixed.