"Also, players who have previously purchased the digital version of games from the original PlayStation and PSP generation will not have to make a separate purchase or sign up to PlayStation Plus to play these titles on PS4 or PS5. When these titles are released for PS4 and PS5, players can head to PlayStation Store and download a version for the consoles at no extra cost if they already own the digital version of the title. Some of the titles will also be available for individual purchase."
That's a big win. I've bought a few games on PS1 games on PSN (PS3). Thought they'd forgotten about those, and we'd have to re purchase them