I've learned there's some recent hiccups with this game because of the recent Old Games Preservation program. I'm wondering what's the state of things now for Dragon Age Origins in particular. Is it still playable on modern systems? Is it still better than the Steam or EA Origin version?

https://www.gog.com/forum/dragon_age_origins_ultimate_edition

From what I have read they've fixed the DLC issues the game had after the update(I can see it mentioned on the game store page too). Everything else is working as it was. They also kept that CPU change they did which cause problems for some people ("Limited the game to 2 CPU cores to boost performance and stability."). If you have any framerate issues it could be from this change which u can undo in several ways.

It's fine on Win10, and it's always been. Why upgrade?

I actually have the EA version installed. a bit modded of course with the addition of LAA. I could not watch ingame videos without! But nothing else. We could really do with a proper Xbox controller implementation, though! Couldn't find that one.

I'm sure GoGs's version is still champ!

Here even the current build is fully playable with all extra content enabled and no noticeable performance problems.

Disclaimer: I do not play on Windows.

Because for some people limiting the cores available can reduce the amount of crashes and improve performance, but it's not an universal fix that needed to be implemented for absolutely everyone (unlike the Large address aware patch) so GOG messed up there