Federated directories are a good feature, and go a long way towards solving the discovery problem that has long plagued federated social networks.

It sounds like Gargron might have had some blind spots in developing this for Mastodon, but I'm not sure the backlash is entirely warranted. There are probably some implementation details that need fixing, like sorting, or hiding directory results of people who are blocking your instance.

I saw someone earlier say that he's trying to make Mastodon more like corporate social networks to appeal to new users and replicate some of the not-so-nice things that social media entails. This could be true when we talk about trending, but it's false when discussing opt-in user directories.

After about a decade in this space, I can safely say that this kind of feature actually would solve a long-held problem in the space that really does make it hard for new people to find each other. It's probably one of the only ways to actually solve it. We just have to make sure it doesn't suck.