Some emulators support things like upscaling, texture filtering, anti aliasing etc there is usually a debate between purists and those who want to take advantag

Some emulators support things like upscaling, texture filtering, anti aliasing etc there is usually a debate between purists and those who want to take advantage of what modern hardware can provide without having to change the actual code of the games they emulate. I think the motivation is still primarily preservation and for the heck of it, emulation development is probably one of the best ways to learn/improve your programming skills since it requires you to learn and understand a lot of low level concepts that are often abstracted by even low level languages e.g. opcodes and interrupts, also it somewhat forces you to continuing being aware of hardware development because new hardware tends to brake VMs/Emulators quite often as ISA implementations change in a manner that usually doesn’t impact most other applications. Backward compatibility isn’t really available outside of remasters and “retro” versions that are often have some minor changes that can impact gameplay (e.g. vsync/frame rate changes can have impact on games that use immunity frames) and most importantly they don’t allow you to use your existing library of games. The PS2 production ended somewhere in in 2012 (which is insane) and even with 155 million units sold it won’t be out there forever so people want to ensure that the games could still be playable in the future.