What hypotheticals? The lead designer is telling you completing the Pokédex and going into Wild Areas are the main sources of Post-Game. From a purely design PoV, QoL improvements are nothing is there's no content to reinforce them. Dark Souls II, even with its infamous Soul Level mechanic, is way ahead of Dark Souls and Demon's Souls in regards to QoL additions. Is it better? We can surely argue about it. Why do I use Dark Souls as an example? There isn't a particular reason, I just like the idea of proving a point by using the most influential (action game) aRPG/Dungeon Crawler of our decade. Pokémon is no different.
Multiple profiles per game and ui improvements are good, but they are mandatory in a hardware like the Switch. In fact, the multiple profiles per game are a characteristic of the Nintendo Switch and no the games themselves. Are we for real treat it like a glorious adition when literaly every game on Nintendo Switch have this feature due to the hardware itself? No. We haven't seen anything great about the game's content, and I say anything. For what we know, there's no Battle Frontier and I'm seriously doubting there'll be even a Battle Tower/Maison/Tree/this-game's-iteration. And this thought is backed up by what I infer Ohmori is telling us with his very own words, not a hyphotesis.
But I like to bet. I'd say Sword and Shield entire Post-Game will revolve around Wild Areas and completing the Pokédex. No Pokéwoods, no DPPl Underground, no Secret Bases, no RSE or even DPPl contests, no Pokéathlon (in a game that have announced the 'Sports' topic the most of any Pokémon game til this moment) and this is for sure, no Battle Frontier of any kind, which all the community have been asking for since IV Gen and they gave us a joke paperboard Battle Tower in ORAS. So after finishing the games and having all your Pokémon transferred there'll be no reason to keep playing the games for 'in-game content' apart from breeding, which has been the one mechanic that has sustained the entire franchise post-game after BW2.
If I'm wrong I'll gladly come back and pick my 'Owned', I hope I'm wrong but at the same time I know I'm not. And this words from Ohmori don't clear my doubts.