@bwv812 wrote:
OK, discard the attachment and the 50/1.8 Nikkor. 7/20 is slim pickings? That's one-third of the lenses in the top 20. More than two-thirds of the Nikon lineup is over $200, and the same can be said of Canon. If anything, the top-20 reflects the understandable fact that cheaper lenses are bigger sellers than expensive lenses. Talking about how individual lenses can run into the thousands of dollars (and tens of thousands, and even hundreds of thousands) isn't hugely relevant to what the market actually is, any more than talking about million-dollar cars says much about the car market as a whole.
And what does it say about the lens-buying habits of entry-level DSLR owners that the second-highest-selling Nikon lens won't even AF on entry-level DSLRs?
What is true is that someone who owns a professional-level lens likely owns a number of lenses, and has made a considerable investment in photography gear. They are unlikely to balk at spending another few hundred dollars to step up to a mid-level body. It's even more likely they will plump for a full-frame body, since most expensive/professional lenses are designed to cover the full frame and you're paying for the privilege.
Unlike Kai Wong's humorous take on the issue, I've never seen anyone pair a $5,000 body with a used Sigma super-zoom; a $500 body with two L-series lenses that together cost $4,000, cover the same focal range, and don't go wider than the FF equivalent of 36mm is also an unlikely kit. A full-frame 6D and the 24-105/4 would be a more realistic combination than either, for half the money.
I don't understand how Kai's video really contradicted anything I said, such as that entry-level bodies tend to have great IQ these days. Plus, as Kai says, most lenses these days are actually pretty decent.