Yeah it is only crypto that increased the ratio of online gambling.
Online gambling includes both fiat and crypto gambling. If you look into the industry then it is evident that crypto is still having a cult following and thus less popular among people. Fiat gambling is still the bigger one.
Now many people gamble with their holding because they want to make more and more money in less time but it is their thoughts and nothing more.Finally they lose all their money and their wallets have been cleaned up by site controllers. Better not to gamble with your holdings.
Someone who is holding coins has some idea behind holding it. They are probably looking the price to moon in order to sell in future. If they have made up their mind then would not waste the coins on gambling. After all I dont expect an experienced trader to fall prey of the gambling vicious cycle. But then again there are exceptions.