>>36609473>>36609482There's no in-game evidence whatsoever that indicates the protags write the entries. On the other hand, every other piece of source material in the franchise (anime, manga, etc) all have Pokedexes with advanced, talking AI that appears to be self-aware. Therefore it's not unreasonable to believe that Pokdexes in the games would be any different.
>inb4 hurr durr only games matterSimply put, the Pokedex's AI comes up with the entries after witnessing a new species. If the Pokedex says Macargo is hotter than the sun's surface, than it actually is. It sounds ridiculous, but the Pokemon universe is as whimsical as it gets. There's no reason to question it and ruin the fun with your lame explanations.