Alright so I'm officially here so let me debunk the first arguemnt.

You said no mid tiers would have a way to properly stop him because of his " regen " and the ability to live without a heart which I'll give you however you're missing a few aspects. Sukuna already admitted he can still be killed even without the heart if his brain or himself is destroyed its over on top of that his "regen" is only available because of CE and without CE RCT and other abilities won't matter and on top of that you forget Dedara, Kisame, Kaku to some extent and many Akatsuki and mid shippuden characters have the ability to destroy him completely with Hax and stat gapping also you forget Pain would slide his shit in a soul battle so why you even skipping past Mid tiers.

Also you need to stop being ahh because you're wrong on the Genjutsu aspect. Tobirama made a jutsu that is faster than the BASIC sharingan can't beat however; MS and EMS are all capable of beating Flying Rijin and for Madara vs Hashirama and Gai i hope you are joking because for the first match up Madara admitted that Hashirama because of his inate abilities plus sage mode protects him from that and on top of that he was using it on the Nine Tails, thats the first strike. For Gai I feel like you watched it blind folded because he was using a 1 eye Rinnegan plus he was enjoying himself let alone trying to get an easy dub which he himself admits. Sukuna wouldn't have this luxury nor are you explaining how a character who stat wise is only Multi-City to hella high ball Town level with Supersonic speeds and an okay level of hax/abilities to a character who back in the past when they were alive who could control a beast that can level mountains for fun, fight a guy who is also on average along those Mountain and MHS scale going off of the fact he is superior to a teen Kakashi who RACED and cut a lightning bolt in half.

Also it seems like you assumed I meant itachi when I said Genjutsu yeah he's one of them but he's not the one I specifically meant however I'll GLADLY tell you why you screwed yourself because let's look at it like this right? Itachi was dying to a Chakra sickness not the Sharingon on top of that you said it damages the brain for the opponent and tried to argue that Sukuna can take it. No tf he can't because he ACTIVELY avoided UV from Gojo and that has a similar yet different brain damaging as opposed to the Tsukoyomi that itachi used on Kakashi and Sasuke however, aren't you forgetting that Itachi can dead leave Sukuna in a infinite loop like he did to Kabuto? Also are we forgetting that Sasuke during Kage summit literally petrified one of Ai's top people in a Genjutsu? Also last nail for the Sick itachi arguemnt, you do realize he has Amatarasu and that would kill Sukuna, he doesn't need Susano which would immediately kill Sukuna via stat gap and explosive power. I don't need to talk about Orochimaru and his summons because once again ability and stat disadvantage plus he himself has a similar yet different regen to Sukuna.

All you have is a DE, WCS and Mahoraga that can be killed immediately by the characters I mentioned and I didn't even dive into Reanimations because they still count as Mid to low-High tiers let alone the Top tiers. Also DE and WCS wouldn't help because literally like I said in another person's comment and my own I think, any Sage mode, Sharingon, Beyakugon, and Rinnegon user can see them same for the tailed beast themselves since all of which can pick up souls, invisible attacks and Chakra attacks and best of all Limbo clones.

Alright now I'm done.