Very interesting. I'd also argue that some of the glitches in Colours Ultimate apparently were on emulators (since usually they aren't perfectly accurate since the console is still currently updated and how the game got leaker earlier).
I'd still argue that even if SA1 and SA2 on the Dreamcast had better visuals I'd prefer a better framerate and skipping cutscenes for the first game and the new additions for the sequel.
Furthermore that doesn't remove the fact that both game had emerald hunting and the first had fishing.