Episodic post-game is never going to be more than a few hours. We have never had real extensive post game besides in G/S and HGSS. Real Pokemon "post game" is breeding and online battles, both of which have been crippled by drastically reduced Pokemon pools and pay to play online services.I'm willing to give GF the benefit of the doubt that they put what they felt was a lot of heart and effort into the games and that they decided to stop supporting all the mons to improve other aspects of the game. My concern is that the bulk of that redirected effort went into aspects like Pokemon Camp or the Currydex instead of postgame content that better warrants the extra $20 on top of a 3DS game. While not much has been leaked about the postgame so far, what has been claimed admittedly doesn't sound like it's more than the 3DS adventure.
I would really love it if GF released postgame episodes through DLC periodically, but I'm not going to hold my breath that they have such plans and are just being stupidly secretive about them. Like, I enjoyed refresh well enough in gen 7, but I didn't use it that much and I am skeptical that I will spend any time making curry unless it's really useful for EV training or something.
Overall, I'm still pretty excited for the game and a lot of the new mons, but definitely concerned about whether GF put enough effort into the parts of the game I care about to make up for the lack of mons I care about.
I don't care if Gamefreak adds in some post game quest that takes a few hours to grind through. Give us real post game activities like a battle frontier, interactive breeding, good online play, decorative houses etc. More likely than not if Gamefreak was so stressed that they couldn't even finish half the Pokedex I doubt we'll see much more than a few hours of post-game content.