Okay i figured out myself, i was using the wrong path for the Collection. When the files of the Playlist were were also in the collection the counting started to work.
Its been literal years that i wanted to see this feature working, i didnt expect it to be such a simple thing, the main problem is that its not intuitive at all, a label or something saying "songs from the current playlist will only increment the playcount if they are part of a collection" would have helped for sure.
I will leave this post here just in case anyone has this same issue. I dont see a button to close it though, so i'll leave it open.