Why is the "stream" so low though in terms of getting more back catalogue games out onto the PS4 and Xbox-one, in the absence of any decent demos and the barren months till August it'd be great to get into some more PS2/1 classics....
Reluctance from third parties unsure if the cost will be worth the revenue.
I also think Sony is reluctant to put out any of their first party games that had a most likely superior release as a "Classics HD" on the PS3.
Edit: Beyond that, lots of games had things like licensed soundtrack, licensed ip, licensed vehicles and other stuff that would restrict a digital re-release without renegotiating a license. There's work involved in that process, and it might not even result in being able to re-release. Publishers could be averse to this risk.
There's also a few publishers from this era that are no longer around, some games that it's not entirely clear who owns them due to assets and ownership changing hands, and a handful of games that probably couldn't be re-released for legal reasons (Psi-Ops comes to mind).
