Most people do know that 15F is significantly above basically everyone in the verse but a lot of people actually believe that anyone outside of Gojo is actually comparable to that Sukuna while that just isn't true. First of all let's address the most logical argument that should already be enough but some don't believe it for some reason.

1.It's a 75% Sukuna minus the extra arms, height and mouth... you have a problem if you genuinely believe Sukuna would be considered the absolute strongest in history but would need to go at 70+% to defeat anyone who isn't Gojo Satoru...

2.Second argument/first developed argument. Sukuna is stated by Yuta's own words to have over twice as much CE as him at 20F meaning 10F in terms of CE is above Yuta and sure CE reserves might be a sort of dubious argument but considering Sukuna has monstrous output, efficiency and lethal techniques that also should be enough by itself.

3.3F Sukuna and heavily suppressed 16F Sukuna being above Maki and Toji. A heavily suppressed Meguna who wasn't going all out could casually nearly outpace Maki with bloodlusted CG Yuji's help... again should be enough to say that 15F>>verse excluding Gojo and 20F but let's just keep on going!

4.Completely violating Jogo who's somewhat comparable to Toji and just the general HH. Dagon can somewhat react to Toji's attacks and Jogo is massively above said Dagon and also he is stated arguably above 3F as well arguing again relativity with Toji and Maki who are top 5 in speed MINUMUM.

5.Him while heavily weakened and barely trying still outclassing everyone. He blantly states having lower output than when he killed Ryu so literally weaker than 15F and still blitzed Maki before BF amps.

6.One shotting and blitzing Ryu while arguably suppressed and very likely still holding back in a weaker body. Same Ryu more durable than Shinjuku Yuji pre-awakening and domain-amped Yuta and same Yuta having struggled against Ryu and no Shinjuku Yuta isn't that much stronger than in Sendai that he would be blitz tier above Ryu...

7.Relativity to Gojo. That one some may say is questionable but i don't care it's just true bro. Blocks a punch from unsealed Gojo in a weaker body, Jogo directly compared him to Gojo and Jogo is used as a scale to also compare Sukuna at that point to Gojo even further. As well as Kenjaku stating that he is inferior to 14F Sukuna even with all the DC spirits and Choso and that Sukuna being able to stall Shibuya Gojo and yes Kenjaku definitely has enough knowledge over Gojo to be considered reliable...

8. The list just goes on and on and on and on... genuinely there's also a whole bunch of other arguments as well to back that up but I'm too lazy ngl to actually make a genuine 15F Sukuna super post... yes i know some of the scans i referred to are missing. Give a BREAK it's fucking 23:23 rn.

Kind of dumb post but 15F Sukuna is MASSIVELY above everyone within JJK outside if 16-20F Sukuna and Gojo obviously.