I have a fair few game dev friends that spend so much time ranting about their jobs, so my first reaction to these mandated demos/trials was physical discomfort as I thought about the poor devs having more work added to their plate.
That said I have heard, and this may not be accurate, but I have heard that the PlayStation Store team will be making these trials/demos, which likely means they'll just be the full game with a 2+ hour timer added to them.
Anything that helps the customer, while not adding even more work to devs plates is a good thing. I initially had trepidations about it, but if the PlayStation Store team are handling this then it's a win/win for everyone involved.