I don’t dispute that you can get real money out the far end but even if you ignore the problematic aspects of crypto as a technology you still have to deal with the problematic aspects of it as a currency including rapid fluctuations in value and the time it takes to settle a transaction.
I guess that could a bit annoying at times, but ad revenue isn't some super precise amount. Price fluctuations should balance themselves out, and the minor settle time is not a big deal when you're typically paid monthly.