Things still not right at my end either. I've got 4 Apple things - iMac, iPhone, iPad and ATV - all with their own version of the same play-count based playlist. The 'closest' are the ones on the ATV and on the iMac, though still several songs off.
(For new readers) The playlist is a simple one, (currently) if it's been played less than 4 times, it's in the playlist, when it gets a 5th play, it is removed from the playlist. In theory, automatically.
I'm running the latest and greatest versions of all relevant software, logged in to the same, the only, account I have for Apple Music.
The latest problems I've identified that may have something to do with it are: the 'recently played' folder on the Apple Music on iMac, only seems to show recently played on Wi-Fi, I can check as (now) Last.fm actually updates and shows songs played while out of the house. And, I'm wondering if a song or two have got the playlist 'stuck' on iPad, iPhone, ATV. There was one time a while back, where I physically deleted a song that had been stuck at the top of the list on iPhone for months, despite repeated plays, and it updated the list...for a while anyway.
All this comes a long way down The List - after world peace, ending world hunger - but, is insanely irritating none the less. And, goes directly against Apple's 'update across your iDevices' claim.