An argument can be made that such attire is restrictive and cumbersome for tennis at the elite level. Being an athletic sport.
That argument can't be made for pool.
Yeah, these guys can fancy themselves athletes all they want. They are not.
Does better attire restrict the ability to stroke a cue? No.
Does it restrict the ability to break? No.
Does it make reaching for shots more difficult? No.
Are pool players drenched in sweat, playing outdoors in the sun in 90 degree weather? No.
Business casual or even formal wear is not some kind of body constraining, performance hindering factor.
A collared shirt, oh my --- these pros won't be able to play their best with that pesky collar.
A tucked in shirt? With a belt! Heck, some prefer that when playing All-Fouls ...
Slacks? They can still just as easily throw a leg up on the table to reach a shot - but we'll be spared seeing their hairy leg or crotch shot.
We can't burden these high-performance, ultra-elite "cue sports" "athletes" with an expectation of wearing clothing similar to that of golf pros. Speaking of which, they don't seem to have much of a problem performing with that dress code.
Everyone has an "opinion".
I have no problem wearing whatever they dictate, but unless YOU are the promoter, you are nothing more than another player with an "opinion" who wishes to be the fashion police.
This is DCC and the events are being shown on PPV. This isn't a World Event being shown on satellites over the entire world with millions watching. This is more of a carnival atmosphere.
Like I said before, I don't have a problem with whomever running the tournament thinks I should wear, but I do have a problem with another player trying to dictate what I wear.
And, FWIW, I have a ton of nice shirts with "band" collars that I think look a LOT more dressy and classy than some golf polo with a "floppy" collar.
When I lived in the Philippines, I used to have shirts made just for shooting pool. They had front chest pockets and waist-level pockets on both sides. They were looser around the armpits and body than a regular shirt, but not baggy. They had collars and looked similar to an Aloha shirt, but without designs...they were plain white or light beige. The pockets gave me plenty of places to stash my gambling money, chalk, cigarettes, etc. and the looseness let me contort into whatever position I needed to when stretching over the table.