In a slightly different timeline, Psyduck wasn't yellow.
What does this matter?
Well, Psyduck would have had the Let's Go game instead of Eevee since Psyduck was the first choice and was denied because Psyduck was yellow like Pikachu.
This in turn would have resulted in Psyduck getting a Gigantamax instead of Eevee in Sword and Shield since it would have been from a gift Psyduck for having data on Let's Go! Psyduck.
And we'd deadass be debating about the idea of Psyduck being in Smash now.
The moral of the story? Sometimes it ain't mellow being yellow, fellow.