To everyone asking "what else works better," I remember using Product Studio at Microsoft, which was a thin client over an SQL database. It had some flexibility problems, but it was so, so fast. It's the only ticket management system I've ever used that didn't feel like it was getting in the way. Unfortunately, about 10 years ago Microsoft chose to modernize/dogfood on Team Foundation Server, which was just awful, probably worse than JIRA. I have no idea what they're using nowadays.

I wonder if the performance we got out of Product Studio had more to do with having a locally hosted instance, vs. running in the cloud, and I wonder if teams that host their own JIRA/Confluence/Bitbucket servers have a better experience. I do find that one of the major gripes people have with planning tools is that they break flow, and I wonder how much of that comes just from the amount of stamina required to maintain focus while waiting for all the spinners.