Why would that be the case?
Somehow, you've got to do a billion dollars in cash to bitcoin transactions, but what's the point of buying middle eastern real estate with the bitcoin after that? Why not just rinse the bitcoin through a tumbler and sell it on an exchange and tell the taxation ministry that you simply made a great investment? Then you have a billion dollars minus tax in your bank account that you can do anything with. Dubai real estate is completely irrelevant to the process.
I think "money laundering" is like "ponzi scheme". The more likely someone on the internet is to use it, the less likely it is that they actually understand the term.
You could take your bitcoin and sell it on an exchange as you suggest but there are two problems with this. First, it's not that easy to sell a lot of bitcoin for real USD and the transaction costs can get high. Second, and more importantly, as money launder what you really want to do is take your dirty money in one jurisdiction and take it to another. Did you ever see Blow? Based on a true story. A US guy raised incredible money selling cocaine and stored it in a shady Panama Bank. The bank steals his money. What his recourse? If you are an oligarch in a corrupt country you want to get your money somewhere your government can't seize it. So why not take your bit coin and use it to buy real estate in Dubai? If you took your bitcoin and sold it in a way that ends up in a western bank, that bank is going to do kyc and defeats the whole purpose.
Obviously I have never laundered money and I don't really know. Tell me I am crazy.
Too risky for me, but if you're a drug cartel, that's business as usual.
Furthermore, when people bring up the laundering and crime argument, I always point out that the us dollar is by far the medium of choice for laundering money, crime, ransom, extortion, drug payments, human trafficking payments, terror financing.
Accepted almost everywhere, virtually untraceable.