Yes, and thinking, that @supports selector is also suggested in one of the examples in the article:

  /* Warning message 
     about support for :has() */

  @supports selector(:has(img)) {
    body small {
      display: none;
    }
  }

And I sure love it when CSS performs according my preference, but I'd never complain about a UA not implementing or a user prefer her own style over agent or author.