The future of mixing, and indeed many other services, is in proper decentralisation. I think it's pretty safe to say that in this area centralisation has largely proven to be a liability, not an asset.
It'll be interesting to see if centralised exchanges will identify and reject coins put through decentralised services. And privacy coins could go either way.
Fincen released a statement that wasn't completely derogatory about privacy coins. I think they recognise that it's not an automatic evil. There will be a need for such thing in future. Fincen also made the distinction between hosted services like Bitblender and those who develop mixing software.
https://coincenter.org/entry/fincen-s-new-cryptocurrency-guidance-matches-coin-center-recommendations