We have to accept the fact that centralized exchanges can easily imposed regulations, restrictions and requirements for their users and there is nothing we can do but to follow them, otherwise the best thing to do is to find alternative platforms that can cater to our needs. I don't see this development affecting the fungibility of Bitcoin, at any rate. I am sure we still have (and more in the future) of platforms that do not care if you are availing of mixing services or not.
Centralized and government-approved exchanges have to be careful in all facets of their business because they don't want any agency of the agency taking notice which can surely affect their business and ability to be making big bucks.