The thing is, if you think about it, glitches usually have to do with processor timings and tiny little miniscule 'holes' in code that appear when they shouldn't, often depending on hardware or some other factor (eg PAL and NTSC). Keeping glitches in a VERY improved systems would usually mean explicitly writing code to ensure the hole - which would otherwise be fixed being executed in a different environment - remains.

"Keeping glitches" isn't necessarily a simple thing. These days it would be more like emulating glitches, and in those cases they likely won't work 100% precisely the same.
They're called glitches for a reason :)