Mfw Snorlax happens to be my favourite Pokemon.
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Anyway, Pikachu would be a notable one with how heavily it's inserted into marketing even when not really calling for it, to the point things like its Z-Moves or the buffs it get in Let's Go make it even more useful than its evolution in some ways. The design change makes the business side of its insertion even more evident, with how it got slimmed down heavily for mass appeal (until Gen 8 gave it a callback). I'd even say some of the "Pikachu clones" offer more interesting elements to them, such as Pachirisu having enough potential as a support Pokmon that it managed to be competitvely viable in Gen 4, Emolga having an interesting basis to its design and offering a good typing that made the gym battle against Elesa a real challenge and Mimikyu not only having a great typing and ability, but has a backstory that allows copying Pikachu to elevate it.
Also, whilst I don't hate it, Charizard is definitely overrated with the special treatment it gets just because it looks cool such as getting two mega evolutions (at least Mewtwo has the excuse of being a genetic experiment gone awry) and being the only Kanto starter that didn't need to be DLC in Gen 8. It doesn't help that, despite how much it's plastered over merchandise, it isn't even that good outside of its Megas and Gigantamax. Rock type attacks oneshot it and it's the one starter that truly makes the game playing on hard mode with how useless it is for the first two gyms, as well as later being useless against Giovanni's team. Also, getting a Pokemon that looks like a dragon and can breathe fire isn't the most creative idea.
There's also a few legendaries I'm not a fan of, though don't hate. Zapdos is the only one of the legendary birds I care for, Suicune's never stood out to me much compared to its two peers and the eon duo don't really offer much beyond being the first psychic/dragons.