As much as I do hate rendering my information at the mercy of the casinos I use for gamble, I have have as well come to that point where I have made this understanding with myself that there are no casinos that are absolutely decentralised irrespective of what they might preach on their site. If they didn't request from the onset then it will just be a matter of when... Because they will at a certain point do. For those that leaves their money maybe it wasn't a jackpot win.
It's pretty much inevitable to avoid KYC altogether, if you take into account how many platforms have our details, casinos should be the list of our worries. However, that doesn't mean we shouldn't try to avoid it when possible. I've personally submitted KYC, BetPanda didn't ask for it initially, but I preferred to be done with it as it would ask me eventually. I've heard that there are decentralised options, but I've never bothered to investigate them.