>>33474390It isn't. Back when HOENN CONFIRMED was still a thing, criticism of the Gen 3 games were everywhere, about as much as there is of XY and SM right now. The biggest complaints, as much as I can remember, were of long and tedious water routes with poor distribution (a complaint I still see pop up from time to time) and trumpets being a terrible choice for the GBA soundfont (a complete 180 nowadays, I see a ton of praise for the OST,) it's why the water trumpets meme came about.
There were also some more minor criticisms like the lack of physical/special split despite being totally doable on the GBA, the inability to transfer up pokemon from gen 2, the lack of nighttime, pokemon designs weren't as good, RSE started the formula of basing plots around box legends and some other complaints I can't remember right now.
It wasn't until ORAS that RSE (and FRLG to a lesser extent) became the sacred cow praised to high heaven that it is now.