Having to pay for basic features that competitors like slack/discord have is exactly why the slack community for something is often much bigger these days. Even the larger communities like #node.js are really just 10 regulars.

For example, Elm's slack is vibrant. Elm's IRC channel is dead. This is the reality for most communities I've been joining these days.

And on top of that, the behavior of irccloud from the standpoint of everyone else is identical to that of a bouncer like ZNC. It's yet another hack around the fact that clients don't exist in IRC unless they're online.