[Androzani84]

Here’s what the actual TVTropes website has to say on the matter

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] Kamen Rider Fourze's Yuki was initially a bubbly, hyper, yet smart and thoughtful girl whose grades were almost as good as Kengo's and could impress Chairman Gamou (a former astronaut) with her knowledge of space. This is exaggerated through the series until she becomes an increasingly loud, screechy, childish nuisance who literally believes in imaginary "rocket gods". At peak Flanderization in the Aquarius two-parter, plenty of viewers had gotten so sick of Yuki that they wanted her kicked out of the Kamen Rider Club and replaced by the Monster of the Week, who likewise despises Yuki for treating space exploration like a joke. She gets a bit better in the Gemini two-parter, where Yuki almost gets replaced by an Evil Twin, with even her own friends mistrusting her, but for many fans the damage had already been done.
It happens to Gentaro in the movies. During the show, his goal is to befriend everyone at school. This trait is taken Up to Eleven in the movies where he's befriended sentient space goo and a giant, sentient space station.
Likewise, while Gentaro has a fair number of Catch Phrasesnote "UCHUU KITAAAA~!", "Kamen Rider Fourze! Let's do this man-to-man!" and "I'm the man who will befriend everyone, Gentaro Kisaragi!", he was still a well-rounded character. But any time Fourze re-appears in crossover movies and such (especially after Souta Fukushi moved on to other projects), his dialog is 99% those three Catch Phrases repeated endlessly (or variations thereof), and Toei seemingly casts Fake Shemps based off their ability to shout "KITAAAA~!" as loudly as possible rather than actually sounding like Fukushi. [

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