Like i said i'm not underestimating them. You are just overestimating them.
You think because it says intangibility off the akatsuki stand a chance? All the intangibility does is make it so they don't have to defend. They all have high levels of armament haki. It took a island splitting quake from whitebeard to cripple akainu.
Planetary devastation will not catch kizaru. And Idk if you noticed but people like law,doflamingo and the new admiral easily avoid larger meteors. law and dofi aren't on admiral level. Kizaru survived that island nuke at point blank range. Well I should say he escaped it. Even if planetary devastation didn't have a charge time it wouldn't get to them. Lol akainu would just do the same thing he did to jozu's rocks. Set them on fire and launch them as make shift meteors.
None of the characters can survive a kick or attack from the admirals. Saying that is just ridiculous and you know it. NO NARUTO CHARACTER AT BASE IS ABOVE BUILDING LEVEL. Let alone multi building level. Their are only very few and even high tiers like madara was killed by simply stabbing him with a kunai. Kizaru's light beam kick that he fired as a warning shot detroyed a tree towering over the city in sabodi and it was wider and larger than the city by a great deal. And he casually broke it. They are not surviving one hit. I will give you the susano'o being able to take it but it will break if he spams them.
I say obito is the most prominent threat because if he sees that they get taken out he will no to simply kamui his whole self. However if he gets hit first then well game over for him.
The animal path is worthless. All the paths are worthless. They all get the aokiji instant freeze treatment. These admirals can casually out speed a gear second luffy. Itachi, pein and obito stand no chance.
You believe I'm underestimating because someone decided to put these three on their own with high tier heavy hitters who have some degree of hax and high speed, durability and strength. If there are plausible arguments for them versus hashirama and madara how do these mid tiers survive. The only thing that protects hashirama and madara from teh admirals are the godess and perfect susano'o. Without those defenses they would be just as vulnerable to strikes as everyone else.
Also the reason why I don't bring up observation haki is because I have never seen any prominent feats for them with observation haki. Sure we know they should have it but with no prominent feats I will not argue such a thing.
Akainu and Akoji would be defenseless against Chibaku Tensei because for one:
It creates a gravitational orbit that pulls all things into it eventually clustering everything into a mini moon, throwing rocks won't work because they're only going to be pulled back by it because of its suction.
That wasn't a city, that was a town, I remember that because I watched that episode when it came out.
Obito isn't a threat, he's not going to touch Akainu or Aokiji in the risk of losing his arm or worse.
Pein, Itachi, and Obito are all hypersonic+ so speed is out of the equation. If we were to equalize their energies, this would make Preta Path's abilities far more dangerous because it can absorb chakra elements leaving the admirals vulnerable to dying from absorption.
Madara and Hashirama are entirely on a different level than the Admirals are, they're arguably stronger by a long shot (Excluding Kizaru.) Madara wouldn't need PS to defeat someone like Akainu or Akoiji, all he has to do is absorb them or crush them with a meteorite.
Given your last statement, this verifies that Genjutsu would work then, if that's the case, the Admirals are going to have a harder time in beating the Akatsuki than before given Itachi's genjutsu.
Also, if any were to die, as stated earlier, Pein could resurrect them as he did with the Leaf Village and his Paths.
I'm not saying the Akatsuki would win but the Admirals are likely going to have a difficult time in beating the Akatsuki because of their hax'ness. The admirals likely win because of Kizaru, he's the true threat here.