I believe telling users not to use a certain relay because they're not able to send DMs with that relay is setting us up for failure. That said, I do believe in having specialized relays, such as a search relay or a media relay, but eventually we're going to get too granular for most people and it's going to provide a less than optimal or bad experience. How many specialized relays do we need before that number becomes too complicated for most users to use? Nostr is already seen as too technical or too complicated for most. I think we should work on making that experience as smooth as possible for mass adoption.