I maintain that Pokemon starts to make a lot more sense when you stop thinking of the Professors as biologists and start thinking of them as children’s science communicators, which, in a world where children as young as 10 are expected to make their way in a world populated by superpowered fauna almost entirely alone, stands as an important and laudable career. “There are 150 animals” becomes the in-universe equivalent of “There are three states of matter.” There’s too much information in this field to dump on a grade-schooler all at once, so Professor Oak is here to mete out animal facts as they become relevant in an easy-to-understand way.
That being said, I would love to see what kind of shit the real Pokemon biologists are on. I’m just imagining some disheveled, overcaffienated researcher writing a grant proposal for their study on why certain wingull seem to evolve into pelipper faster when they hatched in the winter or something. There’s bird shit on their glasses. They haven’t left the lighthouse in months. This is their life’s work. Ash Ketchum doesn’t need to know about real Pokémon biology.