Not necessarily a bad thing for individuals, but definitely a bad thing for Internet users as a collective. Some Yahoo Groups are still active and has irreplaceable, valuable information that dates back to 2000.

We should just have stayed with NNTP and usenet in general but it had a big flaw. It could not be controlled by corporations.

It's a miracle that email has survived to this day using open protocols, but they're desperately trying to control that too using all kinds of blacklists and tricks to keep "regular" people out of setting up a private server.