>>35172128No, it doesn't. Most people have limited funding. If you release two big games at the same time then most people are forced to choose.
There's a reason dates change even when you're talking about entirely different games - companies don't want to release their big game alongside another huge entity of a game because it factually hurts start up sales.
The reason it was okay for Smash and OR/AS was because it was different platforms. They specifically released Smash on the 3DS ahead of OR/AS for that same reason.
They've also been purposely staggering their first and second party releases as well as third party exclusives on the Switch specifically to avoid the dead times which occurred with the Wii U.
Not to say this means Pokémon won't happen as well as Smash though... Smash alongside the online service followed by a Pokémon release in October through December is entirely possible and sensible.