I'm a little bit sympathetic, but they've also kinda tried to have it both ways. They spent ages inventing a new protocol for decentralized microblogging, and then ages more before you could actually use a server other than theirs. But DMs is now where they don't want to spend the time up front to do it the right way?
To be fair, they’re a tiny team with a ton of things on their roadmap and limited time to do it all. It seems they’re taking it slow on core stuff that they really need to get right, because it can’t be changed later, while adopting pragmatic solutions for things that users want now and which can be swapped out for better implementations in future.
