The only costume I wanna wear for work is a mascot costume for a sports team that named themselves after an animal.

Nonsense ideology that dates back to medieval times. I subscribed to it for years until I realized it had no bearing on my work. I tell my interns and staff “dress appropriately,” meaning be comfortable - unless we’re meeting with clients, whose expectations may not align.

Dress codes serve as class signifiers. Like most rules of decorum, they're cultural artifacts used to delineate the haves from the have-nots. They don't dislike the fact that Fetterman refuses to wear a suit. They dislike the fact that he dresses like the common people he actually represents. Whereas they dress like the people they represent - capitalist oligarchs. They're wanting to close ranks and keep people from realizing that not everyone in the senate serves the same masters.

People with their little collars and jackets and ties to make them feel important

Isn't the logic that it's an easy thing to use as a sign of conformance? A check to see if you're willing to compromise your personal choices for the groups mandate?

Probably never. People will always judge others based on how they are dressed. We subconsciously attach a certain image of what people should look like. And these dress codes are often enforced by society indirectly. 99% of people would not want to have a lawyer dressed casually to court and will pick someone else even if the alternative is by all accounts not as good as the casually dressed lawyer.

They just don't want to govern.

Yes. They want paychecks without work, responsibility, or blame.

They don't want there to be a government.

No. I see no evidence of that. Every chance people get to raise military or police spending or make up new laws to restrict people's choices, they take it.