I always knew that A) Ages/Seasons has GBA support and B) GBC games are arted to be extremely blowout and oversaturated because the GBC screen was very washed out, but it never occurred to me that GBA-enhanced GBC games desaturate their colors when played in a GBA to be consistent
Seasons raw output with no color correction, booted on a GB Color and then a GB Advance. pretty neat, and probably why I didn't even notice the difference as a kid