Dan doesn't like nostr because he's been part of a team working on the same problems. They have thought very hard about all the gotchas and believe that they have a better way and have worked very hard on making their way into official web standards.

Nostr devs took a hard look at some of their suggestions, DIDs for example, and decided they were very complicated and that they would rather keep the nostr protocol as simple as possible so that developers could easily build things with it.

Dan and other web 5 people took offence and now take every opportunity to jump on threads to say that nostr is dumb, will eventually run into the problems that they foresaw, and will have to move to their system to survive.

Maybe they are right but the way that they promote their work, appeal to authority, and constantly attack without actually having anything for devs to build on is very off-putting to me.

Time will tell.