Earlier quoted context omitted.
The bridges are not horrible. But they aren’t super reliable. I have seen them go down for a few days once, generally be a bit slow, forward messages out of order, etc. The free matrix.org server is also overloaded. The paid server is much faster.
Still, bridges do not really solve fragmentation problems the same way compliance with internet standards does. For example bridges break important features like end-to-end encryption.
Having 5 IM apps installed is much preferable to me than 1 worse app. Not sure the situation for XMPP but I have been told its highly fragmented with extensions that not all clients support. If I'm talking with someone, I want a high level of assurance that their client is pretty much the same as mine and that all features work and look roughly the same on both sides.