Compare these phyrexians to the ones we actually got on the cards in ONE.
This was the set that made me completely check out of "in-universe" magic, because it was the most glaring and obvious showcase of just how
bad their art director is.
The Scars block had some of the most awesome art in the damn game, which is both endlessly iconic and establishes an incredible tone. Each of the colors had distinct identity and details which identified the art as belonging to that color.
Things get gradually more gruesome as the blocks progress - but it also becomes clear that, as the artists get used to the style, they begin to play and experiment more with what they're working with. The phyrexians have defining features and traits based on their color-identity, and yet they are still full of variety and creativity. And then you look at
ONE. It's flanderized to hell and back, and the main 'tell' of what color a card is... is that all cards in that color share an identical visual gimmick.
Without block-sets, you can't trust your artists to grow and evolve and explore, because it's one-and-done. There's also such a clear and heightened influence on repeated visual motifs: blue has the stupid eye-stalks, white has the red-white color-contrast, black has extra limbs and unordered sinew, red has 'magma' billowing out from threaded torsos, green has massive headpieces and lots of pointy bits. The art director specified: this is how it looks. This is how I want it to look. This is how it needs to look, and your artists churn out sludge. When we move into the hat-sets era, this becomes even more apparent -- but so too is it apparent in "authentic" magic sets like Tarkir, where the factions have all had dramatic reworks to be more generic, less offensive, and way more uniform (and uninteresting) than the original block.
It's obvious that
this guy got promoted into the art director role, and doesn't trust the artists. It's surprising to me that some
legacy artists are still allowed to do their thing - but I would guess their seniority lets them say "I'm going to do this, or I'm not going to make a piece for you." You really could replace the mainset art with AI - which is what the "everything must match these specifications and prompts" approach does anyways - and no-one would notice, so long as you had someone catch hand hallucinations.