It could be beneficial but aren't USDT centralized? wouldn't
Yeah it's centralized.
that defeat wanting to gamble anonymously or without a central authority? although I understand gamblers wanting to gamble without worrying that their money would suddenly decrease its value but if they want to gamble without worrying about it why not just gamble on a fiat-based casino? wouldn't that be almost the same thing?
You don't lose your anonymity even if you are using a stable coin as it's still crypto.
The only difference with other assets like bitcoin and ETH from USDT is that it's not volatile, the value is fix and gamblers does not have to worry on the price changes, which I think would attract a lot of gamblers but for crypto in general, I don't think it's beneficial as real crypto assets should be the assets that we are promoting.
Maybe another option for the gamblers, it may be beneficial for some players who are conscious with volatility. But I don't think the addition will have significant effect on the casino itself.