I don't believe so. AFO's statement didn't mean Koichi became some God Tier. He's talking about Koichi only, that power far surpasses what should've been possible for him. The reasoning being is if Koichi, a nobody, got such a massive boost in power, imagine what it'd do to him. That's why he's interested in it.
While I can see your point, I think it's more than that.
AFO as a character NEVER just compliments people, if he's calling something impressive it's because he truly thinks it is.
"Abnormally powerful output." He doesn't say the output is abnormal for Koichi, he's stating the attack itself is Abnormally powerful, if someone of his caliber is calling an attack "abnormally powerful" then it is that, abnormally powerful.
"Surely far more than can be wrung from a singular individual." He's not saying this power is something Koichi shouldn't be capable of using. He's making a general statement, the output of his attacks is considered far more than one person can do. IMO, he's saying no one person can be this powerful.
But the quirk wasn't just boosting Koichi, he was drawing energy from "something" AFO couldn't "conceive." a "domain beyond the singularity". The output of these attacks were so much that AFO wanted to gain access to this domain. If the attacks weren't anything comparable or helpful to him, he wouldn't have no interest in learning how to access it.
Of course, he'd never be capable of achieving that. Koichi didn't just surpass Endeavor, who isn't even mentioned in that scene.
I say Koichi possibly surpassed Endeavor due to AFO considering his output to be too much for a single individual to possess. It's a general statement.
Also, AFO never said Number 6 rivaled All Might at all. I have no idea how you're reaching that conclusion.
It's not outright stated but implied. He asks 6 how would he reach Koichi (who was hiding in a building), and 6 responds to this by powering up.
Afo then states that "Just like" All Might, he'll smash through it or sum like that.
Maybe you should organize your words a little more, it's kind of hard for me to understand what you've put down.
Sorry.