I’d love it if developers would be willing to collaborate using a dedicated project management tool and leave the bug tracker for bugs, but the chances of that happening voluntarily are nil. You gotta go where everyone else already is.
What'd that look like, that's different from what they do now? Trying to imagine what developer input to that would look like. I think a lot of devs already feel like existing PM tools they use for sprint tracking and such are worse than if they pushed more planning into git or somewhere otherwise closer to the code, so getting buy-in might not be so hard if devs got to be a little less heavy in a bunch of not-actually-that-useful-to-them tools on a day to day basis.
I think 1/4 of the challenge is what tool to use and 3/4 is convincing and motivating people to be reliable and forthcoming with accurate information. A good project manager demonstrates he or she can add value, unblock things, escalate and communicate appropriately, and not just be the Project Police.
It's where I think Jira and other do-everything tools that try to be useful to both ICs and management fall down hard, every time I've seen them used. Management wants to see their burndown charts and such. They want projections out months on minimal data. They want to see the performance of people, not teams. Points become BS because everyone knows they're being watched. Totals are missed the first few sprints (of course they are, you're still calibrating WTF a point means for this team and this project!) and management gets pissy, exerts more control, implies ICs are failing at their job, project goes downhill from there. But look, we're Doing Agile! Such professionals we are.