This is a ridiculous, ill-educated statement that shows a lack of understanding of history, art and the facts of Andy Warhol's technical drawing ability.
1. Art and it's ability to effect people's emotion and intellect has never been (and never will be about) the technical ability of the artists alone. Art is as much about ideas and emotion as it is about craft. Especially since the advent of photography.
2. If you ever stand next one of Andy Warhol's pieces you will appreciate the skill he used. For one, they are often huge: his Chairman Mao in the Met takes up a whole wall. If you only ever see a reproduction of an Andy Warhol you will never appreciate this. Also, although he was trying to say something interesting about the mass-production of art you can see that even his prints were hand-produced and often have manual brushwork on them.
3. If you look at his early work you will see that he was a very skilled draughtsman, illustrator and pen & ink-smith. He hand-drew illustration for magazine, adverts & products so was being paid and appreciated for his skill in the tough world of graphic design before he became a renowned artist.
4. It is hard to imagine what the world was like before somebody invented something that became so prevalent that it is now seen as obvious. Every young artists with access to a screen printing machine has a go at making an Andy Warhol-esque print, most courses in screen printing will include a lesson where people make pop-art, repetitions and colourful squares. It seems obvious now. But when Andy Warhol first did it it was a revolution and a revelation. That is why people liked them so much - they were new, pretty, thought-provoking and very clever.
Go to the Met. Look at the canvases. You might be surprised.