Ask HN: What's a good way to choose the team chat for 400 people?

Problem: choosing a team chat that most people are happy with, for 400 people, mostly developers.<p>I know it&#x27;s not easy. But please let me know about different ways that you have seen it done.<p>P.S. : https:&#x2F;&#x2F;xkcd.com&#x2F;1782&#x2F;