I know many bitcoiners oppose the ETF. When stuff like this happens I sure would like to have Blackrock knocking on their door pointing out this is impossible to comply with instead of a bunch of random plebs they were looking for an excuse to lock up anyway.
The upcoming FinCEN rule proposal is much larger than being able to coinjoin or mix UTXOs. It essentially applies to opening Lightning channels and creating new and unique addresses for normal Bitcoin transactions. It's bad.
https://bitcoinmagazine.com/legal/fincen-proposes-insane-special-measures
Discussion
Interesting point. Deep pockets do lobby well.