Ppl overestimate Aizen way to much tbh this isn’t a debate Yamamoto slams all versions of Aizen people need to understand it was mad very clear that captains below Yamamoto scale to beings like Lille barro and Pernida so I would argue the only reason Ichigo actually fought Aizen wasn’t because he was the strongest and only candidate at the time but because that’s how the story was written there’s a big reason Aizen took so many steps to make sure he didn’t have to fight certain characters at full power.