Largely a waste of resources to do individual compatibility porting of PS3 games given SCE already invested in PSNow and that most of the biggest PS3 games are seeing PS4 remasters.
Naturally, this is not ideal for consumers like myself who have close to a hundred PS3 retail games and over a hundred more on my PSN account, but it's not as though I play any of those old games anymore. It just means I need to keep at least one working PS3 in storage for retro gaming.