Probably many users will join casinos for an alternative of mixer.
Who will be stupid enough to use casinos as an alternative of mixer? Why I say using casino as alternative of mixer is stupid?
First, casinos are no longer anonymous especially when it comes to big transactions due to casinos reserve the right to request KYC.
Second, most casino implement 1x-2x wagering requirement for the deposit before players able to request withdrawal, it means that people need to risk the money.
Will those people who want to mix want to risk their money in a casino? I dont think so, although there is a less risky strategy such as betting with 1.01x but there is still a risk to lose the whole amount.
In case someone is lucky enough to bet the whole amount with low risk, I believe casino will consider it as a suspicious activity if the player request withdrawal after betting 1.01x only.
Last but not least, mixing sites will still be available out there IMO, they may no longer exist here in bitcointalk but there are still many other places for them to promote their services.