I don't think clients should assume everyone or most people are joining from bitcointwitter, although that does seem to be the case, it further cements the silo.
I think they do this perhaps unintentionally, perhaps slightly intentionally to retain those users. You see this assumption in user recommendations at onboarding and sidebars of highlighted notes. It screams "hello, bitcointwitter expat, look we have that Natalie Brunel here, and Carla, look Jimmy Song is here... everyone you love is here!" Which imo is totally alienating to anyone outside of this very specific bubble (and even some inside that bubble who are on bitcointwitter but have follows outside of that bubble too).
https://image.nostr.build/5d3af6ea8dc9473a1180c597f69aa90ae5409ca495c69d7e8bad13e6bc100213.jpg
You also see this in responses to the problem people raise of not finding content. The tired response of 'just follow more people' you see in #introductions too. This might be fine if you're coming from bitcointwitter (maybe you want to see a dozen more posts per second of people saying 'stack sats and stay humble' and an ai image of a robot holding a bitcoin, I don't know). But this doesn't help someone looking for other topics. Twitter is bigger than bitcointwitter. People interested in topiary can find that content on twitter, or Herefordshire folklore, an expert in eel migration, or a cultural commentator, or their favourite ayahuasca enema philosopher etc etc. They can find that on wider twitter. No amount of following numbers will help that on nostr. It's not here.... yet. Perhaps recommendations of topic hashtags to follow at the onboarding stage, or RSS feed accounts... or just acknowledging it's not here. I think it's fine to acknowledge this to somehow retain at least a semblance of this not just being a bitcoin telegram group for bitcointourettes.
https://image.nostr.build/53edfb0524086d3a8f5bf8dffe60de177f7436b6eb18c0fed97cffd7e025d228.jpg
