It is so out of touch that not other character's fashion matches it. It is too obvious to ignore they just wanted to make him Dandelion 2.0 but they failed miserably.
That's literally what Volo always looked like in lore, though, for decades - gaudy Bard - if anything, CDPR might have copied the Realms there.

Wrong. Devil is in the details. Volo has always been chubby, long haired dude with it's distinct fashion. BG3 Volo is far different from original Volo. Now, all of a sudden he has bright purple colors, stripes and an east european style fashion. I wonder who he wants to be!
Denying they wanted to make Volo to be Dandelion 2.0 is just willful blindness.