Rule of Cool should be embraced by all who have EMPOWERMENT.
It explains that DM's judgement should override the rules, because it creates a more fun game.
We can post until the end of time, but that's not gonna change anyone's minds. Are any Old Schoolers here willing to run some old school games to show people how it's done???
Depending on where you live, you can attend other gaming cons that are as cool or cooler than Gencon, without fighting for hotel space.
PAX Unplugged is plenty big enough for me, and a lot closer too.
Was there a feedback panel where you could inform the con organizers themselves of the issues? It's usually after closing ceremonies in my experience.
Most cons also send out surveys afterwards. Be sure to fill them out to tell them about your experience.
You're empowered to rename the classes into whatever best fits your game. You are the master of your game table and don't let WOTC tell you "you can't change that"!
May I suggest hiring MichaelSomething's TTRPG Lobbying Service? For a fair market priced fee, MichaelSomething's TTRPG Lobbying Service will organize a large scale campaign to convince WOTC to undertake your preferred action.