For many remote workers, this is the single largest connection they have to their coworkers and work. It is your main communication method you use. I think the argument is that if you define the problem as "all of them let you chat with one another", then they all satisfy it.

But when it's your main communication method, you want people to enjoy it, use it, and want to use it more. You don't want people to avoid communication because they have to use a crappy IM client. These small differences have huge impacts.

I've used all of them in the past, and Teams was, and still is, the one I avoid chatting with someone unless absolutely necessary.