I'm no tech expert but how radically different is the Neo's hardware that devs are going to have to devote a significant amount of resources to making a Neo version? From what I can see, everything is the same with a slight bump in clockspeed or bandwidth. It's not like they need to do anything radically different or extra for the Neo.
People are acting like it's a completely different architecture and devs need to make the same game twice from the ground up. To me it looks more like, enabling some stuff for Neo and disabling others for PS4. And it's not even a matter of scaling up for Neo. Games are built on PCs and scaled down for PS4. They just need to scale it down less for Neo mode.
Correct me if I'm wrong, but my expectation is that if a game runs at a variable 30fps with vsync off on PS4, they'll be able to get it to run at a locked 30fps with vsync on for Neo mode. The difference will be there but it won't be significant. Just my two cents.