I think its mandatory for gambling sites to show proof of money they are holding in reserves
I don't think it is mandatory, but it is good if they want to show proof.I assume they will explain it if you ask the team.
Anyway, don't forget that they didn't force us to gamble on their sites, it is our own intention. So, before we decide to gamble on a certain gambling site, we ideally already checked everything related to the safety to gamble there, including the financial management of the gambling site (including their fund reserve). If everything seems secure enough, you can gamble there. But if it looks unsafety, just leave it and choose another gambling site.
Unless casinos converts all deposits to a stablecoin , excluding UST hahahah , from year to date most of them should be running on a loss as most utilized crypto coins are down by atleast 65% and that includes Bitcoin
Those casinos don't invest in crypto coins, so ideally they convert crypto coins to stable coins or fiats regularly. The team members of the casinos must also know well about crypto, probably they are the people who have a lot of experience in crypto industry. They won't be brave to utilize crypto coins in their casinos if they don't know well crypto coins. So, I'm sure they won't experience a decrease in their fund reserve during the bearish period.