Honest question: why not just use mastadon then?
Discussion
Because nostr is better. Mastodon's (and likely all centralized social media's) capability is a subset of nostr's capabilities, you can have any level of openeness you care for.
Makes sense. I would like to see more experimentation with topical/regional/community relays.
Multiple communties per relay is a mess especially private groups/communities. This is the simplest and most bang for your buck and doesn't need to be perfect. You can have hashtag feeds, why not feeds where you toggle what rooms you care to be in?
this probably explains it most
cc nostr:nprofile1qqsr9cvzwc652r4m83d86ykplrnm9dg5gwdvzzn8ameanlvut35wy3gprpmhxue69uhhwetvvdhk6efwdehhxarj9emkjmn9qyxhwumn8ghj7mn0wvhxcmmvqyg8wumn8ghj7mn0wd68ytnhd9hx2yhtlun nostr:nprofile1qqsw3znfr6vdnxrujezjrhlkqqjlvpcqx79ys7gcph9mkjjsy7zsgygpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhsz8thwden5te0dehhxarj9ekh2arfdeuhwctvd3jhgtnrdakj7qgkwaehxw309ajkgetw9ehx7um5wghxcctwvshspg7dju nostr:nprofile1qqspz8vkaeknfpudjkhmlegtr7qwsyjk6anzw6u2ypx7x3sc2ftzgtspzamhxue69uhhyetvv9ujumn0wd68y6trdqhxgeg9t5nzw on ReasonTV. The interview that put nostr on the map for me and got me on.