Yup, and they think pissing people off is worth it (for their expected benefit). And... they're probably right. People have short term memories and other things to worry about.
We tested Zulip not too long ago, in short - UI is not so good, but in general still useful: https://nixsanctuary.com/zulip-review-through-slack-glasses/
But it’s probably a small amount because SaaS has figured out to basically milk slacktivism. People will complain but pay.