If they want to sell rainbows in the stores, that's one thing. But a
uniform should be a
united form, building a unified image for the team through consistency. If you can't turn on the TV and know who's playing just by looking at the screen, that's not good, IMO. If Notre Dame sometimes swaps green for gold or if Clemson swaps orange for purple that's one thing; it's the same uniform with the complementary colors exchanged. When the Pirates had their "uniform of the day" in the "We are Family" era (21 possible combos) it was still all the same uniform, "black and yellow" to quote Wiz Khalifa*.
But silly designs (looking at you, San Francisco Fog) and random colors blow the whole point, I think. JMO.
* Wiz Khalifa is not to be confused with Sammy Khalifa, the former shortstop for the Pirates.
Wiz may be the better hitter, but perhaps Sammy can actually sing, not just rap.