That's not art, it's craftsmanship.
There's so many essays and books on this subject. This point of view is also a barrier that western artists and art historians use/have used to subjugate or other the works of non western artists.
Marks work is easily identified as some of you have already pointed out. Artwork is neither good nor bad. It is within context its meaning emerges. Mark's work has emerged through skateboarding, and has strengthened its association to skateboarding through the repetition of its presence. It has undergone signification(gained its meaning) in this way. I'm invoking structuralism, and work by Roland Barthes.
tldr Mark's work has influenced the visual vocabulary and language of skateboarding.
Mark is represented by galleries and has a following of collectors. Hoards of skateboarders show up to his shows, but I don't think they're the ones normally buying his work. So that means someone out there is paying thousands for it. I'm pretty sure it isn't trump directly buying, but people working for him have bought Mark's work which indicates it is expected to only increase in value. The realm of high art/collecting is full of names that aren't known by most people anyway.
https://www.wmagazine.com/story/donald-trump-defund-arts-andy-warhol/This article mentions Mark Gonzales being in Trump's collection. Not concrete evidence though.
As an artist myself ( I actually pay my bills with my art ) I think that everyone has the right to make art and sell it for as much as people are willing to pay but, my only concern is that more and more I see underdeveloped styles being pushed on to the market just because the artist is a celebrity or professional skateboarder. In my opinion that's not good for the artist nor the industry. Just like in skateboarding you don’t get good at it out of nowhere,It takes time and practice to develop it and make it became your voice.
I Personally think Mark’s art is overhyped because of who he is but at the same time I do see something really good in there. Maybe he needs less “yes people” around him telling his stuff is great.
Ps. ALL ART IS TRASH.
Patrons can be trash as well. KAWS is wildly successful yet is panned by critics.