[nottorp]

Historically. But not presently.

They could include a software emulator at least for the PS2 (not PS1 because afaik the drive in the PS5 does not read CDs) on the PS5 and let people use old discs, but they don't and instead sell again old games packaged with the emulator in their online store.

[Yeul]

I doubt there is a lot of money in PS2 games. Anyone who really wants to play those games can emulate them on PC.

[lxgr]

Arguably, there not being a lot of money in them would be a point in favor of Sony shipping an emulator (as a minor perk/nod to long-time ecosystem fans), not against it (which would allow them to keep selling "HD remakes" etc.)