The encryption may be the best but constant technical issues really hold it back. I was in a roughly 30 person group and by that point all it was was people sharing different numbers of how many they saw in the group and saying they weren't seeing every message.

It really annoys me the best or nothing attitude to encrypted chat. Simplex or Telegram only. Matrix works great and Signal lets you hide numbers and use aliases now. Still every group is on Telegram because they can't all make simplex work.