That's certainly an argument often made about counterfeit goods, and it can certainly be true in cases (and counterfeiting has other problems, namely confusing the origin of a specific good when that matters to the consumer), but it's also not a universal truth either. Were it a universal truth, that would imply generally that open source can't work because anyone can make and distribute copies of the open material, but also it implies that Windows and macOS should not exist because of all the innumerable Linux clones.
Also instructive would be the IBM BIOS clone, it is perhaps true that the "IBM Compatibles" killed the market that existed for IBM machines at that moment in time, but it's also true that it opened whole new markets, both to the clone makers and the ancillary businesses, but also arguably IBM themselves.
3d printing and Arduino are probably other examples where "counterfeits" might have shrunk the market for the originals (Prusa is notably reducing how open their designs are, and Arduino themselves are not the healthiest, modulo being owned by Qualcom now), but the market for Aruduino projects and ancillary supplies and certainly the market for 3d printers is massively healthy, and arguably both are healthier than if Arduino or Prusa (or really Reprap) were the single and sole providers of their products.
And I think art has an even stronger bulwark in that a lot of the value of a given "art" comes not from the art itself, but from the artist. It's very possible many famous artist's works were actually made by their apprentices, but until someone proves that, the art will continue to have value as an original work of the artist. But art is also a dime a dozen (or less). The internet is full of free or dirt cheap art and today you can go on fiver or mechanical turk and commission any number of artworks for probably less than your day's wages. But no one is buying tickets to your Fiver concert. No one buys $1k per plate dinners at Deviant Art gallery showings. But they will pay many thousands of dollars for a piece of artwork that might destroy itself because the person who produced that artwork is named Banksy.
