Unfortunately, these advantages are gradually fading away due to the fact that the entire crypto comes under the control of corporations and regulatory authorities. In fact, it makes no difference which tool you use if you are completely controllable and transparent at key points.
By the way, how many casinos do you know that use Monero?
I disagree with you, you can still find many sportsbooks like Stake.com for example without KYC. And you don't need Monero or another anonymous coin to stay anonymous. You can use mixers, coinjoins or send your transaction through an exchange with no KYC : you just need to send your BTCs to the exchange and change your BTCs into another cryptocurrency accepted by the sportsbook (ETH, LTC, DOGE, BCH, XRP, TRX, EOS are available on Stake). And if the sportsbook is crap and only accepts BTC you still can do that by using 2 exchanges, on the first you will convert your BTCs into an altcoin that you will send to the other exchange and there you will convert the altcoin into BTC before sending it to the BTC sportsbook. Hence there is no transaction on the blockchain linking your wallet to the sportsbook.
I did not say that there is no longer any way to remain anonymous. I talked about trends - and the fact is that with the arrival of large players in the cryptocurrency, the rules are tightened and the entire industry is moving towards the fiat world. That is why real tools of anonymity (such as Monero) are being squeezed out from everywhere.