It's been getting worse for months, too. Today, I searched for something and the overwhelming majority of listings were comically fraudulent, each with the same price and description. The format is very regular: a price around $100 (not unrealistically low for many used items, but obviously too good to be true for recent-year computers) and identical description text that amounts to "buy this offsite at this hacked shopify URL." For a while I would flag these with the reporting tool, but nothing ever seemed to get taken down. I know it's difficult to moderate at scale but the pasted-in scam content is mechanically blatant and it seems Facebook simply does not care. "Caveat Emptor" doesn't quite do. It's more like "Go fuck yourself, emptors."
It's almost bad enough to send me back to Craigslist and its bizarre propensity to return page after page of industrial refrigerators with humungous advertising text in the images.