This is actually a good thing for FB to go after. These advertisements come from low-income, low-education, and often foreign assholes. This has nothing to do with real cryptos.
but rather are terrible and annoying scams. As a regular author about MLM and its BS (www.themlmsyndrome.blogspot.com), these fake crpyto douchebags have been all over the MLM "business opportunity model".
These things are a gigantic nuisance, and if you need any reference to how awful they are, then check out "One Coin" and what is happening to them (they overtook Amway)