Not sure how much these (marketing) laws are enforced, though. Some 10 years ago, when everyone and their sister tried their hand at drop-shipping, you'd get drowned by these "99% sale" ads, where people would try to sell AliExpress watches/jackets/etc. for $100-$200, with some ridiculous before price. ("Before: $5000 - Now: $100", etc.)
"These are genuine faux sapphire earrings.
14-carat gold, 86-carat faux sapphire.
Faux is French.
It's got an X in it, but you don't pronounce it.
How do you like that for prestigious?"
Sounds like the term has become a bit more general, going by the interpretation you've experienced.