I did compile this some time ago, and the current packages in the 5.9 repo mostly did it (libgnomeui, etc...)
I think I had to compile something else... can't remember what, but I think it was just one or two packages max. besides rythmbox.
So it's possible, and it doesn't take that long. Some features, however, might be missing... I would have to look at it again.
At the time, I thought of submiting it..... too bad I didn't, as I don't know what I did anymore.
For the moment, I'm silly busy with other stuff, so I won't commit to doing it soon.