I'm not. The whole "I hate Jira thing" is a meme among a very vocal minority of tech enthusiasts. They don't have tens of millions of users because Jira is awful. The reason why so many people cry about it (apart from the meme-factor) is that people conflate Jira with their team's failed approach at scrum.
Sure, it has rough edges, and sure, Atlassian as a company sucks. I have a bug report open on their Jira for some 20 years and I don't think it will ever get fixed. And yes, Jira Cloud is very slow, it's ridiculous. And in spite of that, GH Issues is still objectively worse. It's so far behind in terms of features that it isn't even a fair comparison.