Buying "the best" "you can afford" (two separate considerations) is sound advice for beginning quilters. Using tools of superior quality does not boost inherent skill, but using inferior tools and materials can certainly frustrate the process and result in a product that is of lower quality than what might have been made.
A beginning quilter doesn't know what a rotary mat is supposed to be like so she might be discouraged if she has one that "flakes". Likewise if she has thread that breaks in her machine, or fabric that frays terribly, or scissors that don't cut as well as they should. Give her enough "environmental" problems and she'll think QUILTING is the root of the issue because she doesn't know it can be better. How far would you have gotten with painting if your canvases consistently shed enough lint to muck up your paint?
As quilters build their skills and experience they can better tell what a quality tool or material will be because they'll know WHY they're looking for certain things, and then price becomes less of a guideline and more of a project management consideration.
In addition quilts, in general, are not meant to go on a wall or otherwise be handled gently. Quilts go to the park and the beach, they go in the washing machine, they go on beds where kids like to jump. They keep us warm, with both their form and their function. A quilt made with inferior materials (which cannot always be told by price) simply won't last as long or wear as well.
I think you won't hear a lot of objection to your original post because many quilters don't think about "art" -- they think about doing what they love and call it quilting.
Interesting thread.