It has nothing to do with "moving on". A good amount of people chose to play the ps2 version over the ps3 version. You are new here but last year there were numerous threads about it but it isn't as an absurd thought as you are trying to make it out to be.
I very well could be wrong but from what I understand there aren't any devs that could switch from that version to the ps3 version and make a difference.
The ps2 version is simply a port and hasn't been worked on at all since the switch to next gen. The only work that goes into it on a yearly basis is minimal at best.
The reason people chose it last year was because even though that version has basically stood still, the gameplay was still superior to last years next gen version.