That's not the best comparison, HipChat is an ant compared to JIRA, and Atlassian gave up on HipChat only a few years after acquiring it.
You and I must use a very different JIRA.
But then they're never going to look at the UI for Jira either because they're too busy for that.
(Slack is another good example. Slack is "just" an IRC client with better emoji/GIF support. But I'll be damned if Microsoft Teams doesn't _really suck_, even with the benefit of knowing how Slack does everything. Good software is hard and takes work.)
Trello was the counterexample: it implemented less than 20% of Jira's features and was all the more useful for it. (thus Atlassian bought it and have started ruining it with bloat).