It's a give a mouse a cookie situation.when the "patch" is just higher render resolutions and framerates i think free is a fair expectation.
Without bc, all the crossbuy games on ps4 were nice and other ports were just regular ports.
With bc and ps4 pro though, players expect games to run on newer hardware and look better for free. No one paid for ps4 pro patches, so why would they pay for ps5 patches?
I think the big problem is just that next gen games look a lot like current gen games atm. PS5 feels like a ps4 pro pro at this point because so little of next gen has been shown. Come nov with head to head face offs, that could change.
unless i'm mistaken spiderman remastered isn't that. it's the original spiderman game in the entirely reworked city they made for spiderman Miles Morales with higher detailed assets, improved lighting including ray tracing, increased city density, 3D audio, haptic feedback, and of course higher render resolutions and framerates.
https://www.gamespot.com/articles/heres-how-spider-man-remastered-is-improved-on-ps5/1100-6482503/
the original spider man will run on ps5 via BC and while sony has been less clear on what "boost mode" means here i think it basically means higher render resolutions and frame rates. that's a free "upgrade" there.