An exchange doesn't lose anything by listing a shitcoin.

As long as there are poor souls willing to trade it, there will be exchanges willing to list it. It's revenue for them from the fees. Exchanges without values don't care about the future of the coin nor the future of whoever trades it. They just want their cut.

Other companies show some degree of decency and keep it Bitcoin only, even if it means leaving money on the table. Strike, Swan, Cashapp, Peach, Relai, etc. Not saying they are angels, but they are intentionally being Bitcoin only in a world where it pays off to turn yourself into a shitcoin casino a la Binance.