If Akainu gets taken down in the final war where also Imu falls then he's a final villain especially when Luffy will be his oponnent. He's just not THE final villain and i never pretended like he was. Him getting crushed is just an opinion. We're talking about a Manga where a guy like Zoro was put at 100% with Mink cum, I'm not ruling out the possibility that Akainu would push Luffy extremely far.
The Navy will be defeated lead by the crew while the Revolutionary army advance past to the Holy land and fulfill their role as the Scabbards of the final arc.
The way you're describing it, Akainu will be a final villain as in he will be one of the last people Luffy fights, which is about as relevant as Blueno being one of the last people Luffy fought before TS. Dude came after Crocodile and Enel, but still a fodder to them.
If you want Akainu to get any hype from being one of Luffy's opponents, he needs to be a major antagonist, which is only possible if he's the main boss of his own arc. Oda used two Yonko to force Zoro to use the Mink medicine or whatever. You're reading manga the wrong way if you think Luffy will need that kind of shit against Akainu after defeating Kaido, Kizaru, and Blackbeard. I am all for Akainu wank, but he's not that guy.
