The OFAC action against tornadocash and users of tornadocash was a direct response to the use of Tornadocash to launder funds to do with North Korea.[2] You can agree or disagree with this, but the US and OFAC have consistently claimed the right (as most countries do) to intervene to enforce sanctions. They do this in conventional financial transactions, so it doesn't seem out of the ordinary at all that they should do so in crypto transactions especially given that North Korea has been active in using crypto to facilitate sanctions busting (eg [3]).
The fact that the flashbots crowd have decided to use the ofac list as part of compiling blocks in their relay and their relay has become the most popular shows that for the most part validators don't really care that much about enforcing the ability of people who use tornadocash to transact conveniently on the ethereum network. I expect this will reach an equilibrium where tornado users will have to pay to use certain relays that then have to pay more MEV (essentially bribing the validator) to get their blocks confirmed.
[1] https://www.unodc.org/unodc/en/money-laundering/global-progr... [2] https://home.treasury.gov/news/press-releases/jy0916 [3] https://www.bbc.co.uk/news/business-61090064