Heian Era\True Form Sukuna's stats ARE just that insane.
Miguel is conceded by GOJO to be a physical threat in general and even possibly towards himself.
Miguel's physique\physical capacity being praised by Gojo
その中で、日本では珍しいフィジカル、骨格や筋肉を持つミゲルが、呪力強化を備えてるだけで、こっちとしては脅威なわけ。
Gojo - "But among them, Miguel has a physique that's rare in Japan, his bone structure and musculature and just having that combined with cursed energy reinforcement makes him a threat.**”
脅威って、五条先生にとってもですか？
Yuta - "When you say 'a threat,' do you mean even to you, Gojo-Sensei?"
そうだねぇ。伝わるか分かんないけど、僕とミゲルが術式なし、呪力強化ありの身体能力で競ったら、線の動きなら勝てるけど…
**Gojo - "**Yeah, I guess\I suppose so. Not sure if this’ll get the point across, but if Miguel and I were competing using nothing but our physical abilities—with no cursed techniques, just cursed energy reinforcement—I could beat him in straight-line\linear movement… but…”
These do have some different translations, but the primary ones that I've seen in this scene are roughly trying to portray the same thing; Miguel is being stated to be an actual physical threat by Gojo\Gojo is praising Miguel's physical capacity and is even admitting that Miguel CAN pose a threat to him physically. Admittedly; didn't get these scans\translations myself so if these aren't correct I do apologize lmao.
Miguel being made an equal\relative to Gojo
Miguel on entrance to his fight with Sukuna is stated as a "Rival" to Gojo; implying that during their fight in Vol. 0, even when Miguel is told by Geto to merely "buy time" instead of actually properly fighting. This doesn't necessarily indicate that Miguel would have outright WON against Gojo had he went all out\fought with intention to box Gojo, it just means that he would've likely done better against him.
'Rival' --> "To Equal or Match: To possess qualities, beauty, or skill that approach or match another [Gojo]"
Regardless of this being an editors note or not; this is generally just backed up by Gojo not being able to go over to assist Yuta vs. Geto in the manga\LN\movie, but this is the most "up to interpretation" part of this post for sure. Though u/ShalkaScarf certainly could come in and confirm why an editors note is valid..........
Moving on tho: On top of all of this already; Gojo upon just LOOKING at Miguel [albeit through the blindfold] says that he looks like he'd be a "pain in the ass\troublesome" in most translations.
![Miguel having the plan to buy time instead of fighting & being called a pain in the ass by Gojo [Also holy fuck Miguel is so ugly in 0]](https://preview.redd.it/brwuf9y4uwuh1.png?width=444&format=png&auto=webp&s=15f59df937120af7867b71519ee759a30997ac47){kind=link}
Now, this might SEEM like a Miguel glaze post with all of this just talking about him; but I promise
it's not. This ties back into Sukuna lmao
Miguel & Sukuna are shown in 255 to go back and forth; with Miguel having Prayer Song\Hakuna Laana on to buff himself and debuff Sukuna's capacity. This doesn't directly seem like a Sukuna upscale considering he's getting outpaced\outdone by Miguel in H2H, but this Sukuna is still weakened by quite a bit. This Sukuna is shown to still be missing 2 hands which undoubtedly does NOT help his current situation against Miguel.
However, even with all of the various debuffs that this Sukuna currently has; he's still able to somewhat participate in the fight with Miguel & the other sorcerers later in this scene. He's getting pressed and is technically on the backfoot, but again, that can just be due to his injuries.
Semi-TLDR: Any "lacking damage" that Miguel showed in 255 onto Sukuna is merely a TF Sukuna upscale rather than a Miguel or Gojo downscale, and TF Sukuna at full power\full health would just be insane to deal with for anyone; calamities included.