I'll just point out that there isn't any significant inconsistencies between how Kamino AFO and Gunga AFO were portrayed. This isn't from a powerscaling perspective but something anyone can observe.
- Kamino AFO one-shots multiple heroes with an Air Cannon. This isn't too crazy as most of these characters aren't really All Might level, and it was almost surprise attack, and it didn't kill anyone. Best Jeanist is scaled to 6-B only for surviving an attack of that caliber whilst being unable to formally fight afterwards. He gets one-shot by a concentrated Air Cannon.
- Kamino AFO struggled against the team of Endeavor and Edgeshot and failed to kill them. Most people's impression is that he low-diffed them but the way he moves in Kamino and in Gunga aren't really any different. Weakened AFO fights almost stationary, making only the most necessary movements.
- Hence, why Kamino AFO needed to use a large-scale Air Cannon to fend off Edgeshot and Endeavor, which did 0 damage to them. Its purpose was to BFR them so he can focus on All Might. It should be noted that Endeavor wasn't even using Flashfire Fist (possibly because Horikoshi hadn't came up with it yet) and Hellflame was already matching Air Cannon.
- So it comes to no surprise that Gunga AFO modifies his strategy against Endeavor and no longer spams Air Cannon against him, using it against Hawks instead. He strategizes based on exploiting Endeavor's weaknesses.
This isn't inconsistent with All For One being narratively an overwhelming threat in Kamino.
Much like how Gunga AFO still had the edge over a stronger Endeavor and nerfed Hawks, and was only defeated with the help of Jiro, Dark Shadow, and his Quirks rebelling against him.
Kamino AFO probably would've won against Endeavor and Edgeshot after killing All Might. Maybe not as exaggerated as "kill everyone and take Deku's Quirk" but he had the advantage due to having less weaknesses and no solid strategy against him.
In order to build a coherent narrative, a story has to write elements that support it. Fans mistake Kamino AFO's overwhelming aura farming and being the strongest character bar All Might to mean he just solos no-diffs everyone else. If he can do that he would've done so with Edgeshot and Endeavor like he did against Jeanist, Lady, and Orca.
Let alone the fact that Deku, Shoto, and the others overcame that "fear aura" anyways. Stain had similar petrifying aura (albeit weaker than AFO's) that can freeze people, even the likes of Endeavor who can fold him like laundry.
AFO's death aura was certainly a show of power but it isn't a definitive proof of anything.
