In regards to the recent announcement at E3 2019 that only Galar region Pokémon are transferable to Sword & Shield, let me just point out that Nintendo / Game Freak did this in order to help balance the competitive VGC meta due to the power creep from Mega Evolutions and Ultra Beasts in Gen 6 and Gen 7 which they realized was a mistake to begin with. That and everyone was using the exact same Pokémon on their teams to the point where matches became too predictable so they figured If they restricted teams toward Pokémon only available in the Galar PokéDex it would add more creativity by shaking up the meta.
I mean you can't really blame them for it since they had incredible difficulty coming up with a solution to close the power gap between Pokémon whose base stats weren't able to compete with Mega Evolutions and Ultra Beasts to begin with when Dynamax itself was never really intended to solve the issue in the first place. Most people are only going into this from a casual players perspective when Nintendo / Game Freak already covered that in Let's Go Pikachu! / Let's Go Eevee! as Sword & Shield was to some extent designed with VGC in mind going forward.
I won't deny that the balance is off at certain places, but that balance is off at completely different places in different formats. Incineroar is broken in doubles formats, Hoenn legendaries are in VGC, but entirely different things are broken in a 1v1 setting like Breakneck Blitz Porygon-Z. You don't fix the balance of the meta by just kicking out a bunch of stuff, especially since it's highly doubtful that the things they're kicking out were the things broken in the first place.
Like, just nerf Intimidate to only affect one random opponent, or only activate when at full health, or only against targets smaller than you, or whatever, and you bring Incineroar and Salamence and Landorus way back down.
Make Hoenn legendaries Primal weather removable by conventional means, or make Zygarde a bit more viable on the special side and remove Ice Beam from Kyogre. If Land's Wrath were special and Core Enforcer would also work if Zygarde attacks first and it wouldn't have to fear Kyogre's Ice Beam it might actually be somewhat viable. Zygarde is one of those pokemon with tools to shake up the meta like Aura Break to stop Xerneas and Core Enforcer to remove abilities, but then it's weak to Fairy and Ices so in practice it just doesn't work at all.
Nerf Tapus a bit by shortening the time of an active terrain from a surge by a turn and spread the terrain moves a bit wider through tutors.
All of this isn't particularly difficult. They've made changes for balance quite a bit, like nerfing Parental Bond and removing Kangaskhan's Power-Up Punch. Axing pokemon entirely from the game doesn't help things at all.
