It also doesn't mean that Yorkies cannot be selected and bred for small size, given a popular name and sold. Unscrupulous breeders exist for ANY breed that can sell dogs for money, so why should it be any different for unusually small Yorkies? I expect some do it right, and the buyers get what they paid for, and some don't.
Describing the hazards of owning and/or breeding small Yorkies doesn't nullify their existence either. You may just as well say that evil breeders have created a flat faced dog that is prone to eye problems... Don't buy it people! You are being taken! Don't shell out your money even if you like Pugs!
And BTW - the only reference cited by your author is: http://www.moonlightkennels.com/. Did you go there? I tried to; it either doesn't exist, or more likely is the site that states at the top of their web page: "We at Moonlight Kennels and Transport breed only Siberian Huskies". Why would anyone cite them on Yorkies?
Yes of course, I know nothing about the dog world or dog breeding.