I suspect most artists (and I used to be one, at one time[0 - 1]), would take advantage of AI tools. I suspect that the posting was really just exhibitionism, on the part of the site owners (I really wouldn't bother with that kind of thing, myself).

But I think that telling people to do a good job "on their own time," kinda sums up the zeitgeist of today's tech industry.

[0] https://littlegreenviper.com/art/Cavalier.png

[1] https://littlegreenviper.com/art/Sentinels.png