SV's biggest problem are just being painfully unoptimised so giving them a bit more room to breathe on better hardware will improve the situation a bit. I've seen people getting them running better on modded overclocked Switch systems too, the stock Switches really do amplify the problems.
Better specs wouldn't change the fact that the underlying spaghetti code is a liability though, it'll just buy them a bit more time until they hit this wall again in a few games' time, since each game's development cycle basically involves piling more shit on top of the already overwhelming mess from the previous one. Ideally they'd take some time to clean everything up under the hood (and there's a part of me really rainbow-stickering that the radio silence on Z-A has been because they've been working on that), but that's also time-consuming for a series on strict release schedules - especially since Pokémon games need to remain compatible with each other, which is a consideration most JRPGs don't have to worry about.