For example, you can refuse to use Google Chrome, and instead choose Firefox or Vivaldi. Your web experience will be slightly different, but the most important parts will remain the same: You type an address, you wait for it to load, and you access the content.
On the other hand, refusing things like WhatsApp means there's a non-insignificant amount of people that use WhatsApp to communicate exclusively. This may not have impacts for you, personally (although I would be hesitant to believe that), but it definitely leaves out billions of people who communicate exclusively via WhatsApp.
A similar thing happens, for example, if you refuse to use YouTube, which is the largest Internet video platform on the planet: You will have to refuse to watch any content that is only uploaded to YouTube, or put up with frontends that use YouTube in the background, or perhaps even be forced to pirate videos, neither of those three options is good for different reasons.
SMS is about as close as exists for open instant messaging, but it requires a phone number
IRC seems to have inspired Discord and Slack, with the closed variants improving on features and discoverability.
As far as I know, XMPP doesn't really have a cross-server ability like SMS and IRC, though.
E-mail is totally intercompatible, but the experience for anything apart from "the equivalent of letters" is simply horrendous. Delta Chat tries to make e-mail more like a chat app, but it isn't perfect, because e-mail wasn't designed to be a chat application.
XMPP has other massive usability flaws. So does IRC, Matrix, and others.