The series kinda forgot how to be brisk after AAI1. Ace Attorney becomes something different starting with AAI2 (really with the last case of AAI1) where the scale and scope of each game just kept getting bigger. It wasn't enough to have a handful of cases that primarily affect Phoenix's world and not much else anymore. You needed to have Edgeworth solving global conspiracies on a weekly basis, Phoenix and company overhauling the legal system of multiple countries, etc.
Not that those games aren't good, but they're definitely different and that change rubs some people the wrong way.
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