

『Despite All of the time had passed, I still feel as if this feat is a bit underrated』
I feel like The Final Smash is still a bit underrated in terms of feats here, because it upscales Deku (and debatably All Might) by a crap ton.
In total, during this scene, Deku was not only heavily tired and extremely injured during his fight with Shigaraki,but it was to the point where he was struggling to stand, let alone run. And he needed the help of Aoyama and Iida to get a kickstart.
And not only was he the MVP by dealing the most damage to All for One, but he released a massive smash that cleared storms all across Mt. fuji that eventually reached America that affected an entire country, (keep in mind, this punch was aimed straight up and not angled, so the final smash debatably affected more.)
And while Deku did say that in that moment, his One for All was a little bit stronger then the 8th user, (being prime All Might since Deku is the 9th,) it is important to remember that, again, Deku is using the embers here, which is way weaker then base OFA, even if he just recently lost it since he dosen't have the full OFA package anymore, even if we disregard the other quirks, since that's how embers work.
And this feat by itself, would probably immediately KO anyone else in verse if hit head on except maybe Prime Shigaraki and rewind AFO. (rewind AFO is pretty much immortal until he rewinds out of existence, and Shigaraki dosen't use quirks that buff his durability so
So imagine a fresh Deku with all of his quirks doing this same feat with 100% One for All and stacked with all of his other quirks. Absolutely no one is surviving this, and Rewind AFO would probably go from an adult to an child with how much damage this would do, which is why I say this feat is not only underrated, but upscales Deku the absolute max.
Although, in my opinion, it's hard to say how much DC damage would this do with prime Deku, considering OFA percentages aren't exactly linear.