Because the theory behind a monitor is different from real life.
How do you hide your wealth?
This is not about hiding your wealth from other poeple so they don't whose know house this is, this is about hiding your wealth from the IRS.
You go and buy a 30k car, with what money if you're unemployed? You buy a 300k house, again with what money?
It doesn't matter what you used to launder your money, from monero to mixers, you have solved one problem, the tracing from where the coins originated, but you can't hide the physical wealth and you can't hide real-life purchases.
They weren't able to withdraw 178k and 122k in 3 months from an exchange and you're talking about 10 million a month?
Oh, let 50 poeple know that you have billions, and let your family share your prison time.
Do you think Cex and banks and the IRS are stupid? They have reports of poeple withdrawing money from exchanges when they see entire families withdrawing in each of the member's names cash what do you think they will do?
Exactly, contacting stranger after stranger to help you exchange coins to fiat and have that sent to you in a parcel to a PO box won't trigger any flags from them, there won't be anyone ratting you out to the FBI and there won't be anyone blackmailing you after this.