I summon One Hundred-Eyes Dragon!
"With cannabis legal in many states across America, why is it still banned in sports?"
Because it's still illegal at the federal level. A state cannot legalize something that the federal government has banned. We saw that when Alabama and a few other states tried to ban gay marriage at the state level after the Supreme Court ruling. The only difference is Trump and Biden have not bothered to go and bust up these open drug rings.
My younger brother used to work at a dispensary in Colorado. They had to pay him in cash because no federal bank will open an account for them because they are criminals.