Never said that he isn't marketable.
You said Nike wouldn't want him, because he's not marketable enough. No-one said he's more marketable than Federer or Nadal, although as Alis has pointed out, even that is not entirely clear-cut. There's no single measure of "marketability". Different companies will find different qualities desirable. For example, the qualities Moet associate with Fed in their advertising will contrast, or arguably contradict, the qualities Adidas want from Andy. Adidas comes across as more of a functional brand for serious athletes with grit, while Nike strikes me as a bit more style over substance!
I think the article you mean Alis was that Andy scored significantly higher in likeability than Federer, Nadal or Djokovic, but I think overall Federer and Nadal were more widely known. People admired his fighting spirit, although obviously winning eventually is an important part of it.