I’m a fan of Pivotal Tracker for small teams using Scrum. I haven’t used it in a few years, but I don’t think it works well for large teams...I need to revisit.
IMHO, Jira is awful. Looking forward to the other responses.
Same. Pivotal is nice because there's very little to bikeshed, but it's a double edged sword because it can't evolve as your processes get more sophisticated.
Restya has a good contender https://restya.com/core-jira-slack-alternative (Disclosure: I'm on their private beta for the last 2 months). They keep delaying the release and frequently changing the UI.
If you're managing a software project then Apache Bloodhound is excellent and free. Fair warning though it's a geeky product for a geeky use case. If you're managing a screenplay project it would be more work than it's worth.
Youtrack by jetbrains. They have recently introduced new cheaper plans , for small teams it’s really free.
We switched from JIRA. Best decision ever.
Wekan and Notion are, for some reason, the least popular, best options I've found.