don't see anything misleading? A big (claimed) upside of cuDF is it (clams to be) a drop-in replacement of pandas.. only one line needs to be replaced, all of the rest of the code is supposed to be the same. So the manual multi-threaded rewrite , or via dask do not really compare, unless you are ready to factor-in the programmer's effort to learn duckdb and rewrite all existing code into it.
Also the price comparison is weird.. if you are price-conscious, you don't get most expensive device which was just released this year. Find a more common device, and you'll see that the price difference is much smaller.