What I understand on the topic is, Visa and Mastercard were ban as a payment processor for gambling and paypal has also stopped processing online related to gambling, so these are big payment system and there's still a lot of payment system that these gamblers can use for sure.
However, with the absence of these popular payment system, it will present an opportunity for bitcoin to be use as a payment system.
We are only seeing the opportunity here but nothing has been proven yet as for sure government will do something to stop people from accessing easily in gambling sites especially the no regulated ones.