People like to say they're lazy or lack scope, but I think it's more that they have a lot of traditions to uphold and very little reason to change central features. When you have over 800 possible party members in a JRPG, it requires a hell of a lot of scope inherently, and they can't just remove those either, nor does anyone want them to. If you want innovation in gameplay or presentation then I'm sorry but Pokemon mainline games are not for you and are not intended to be for you. They're intended to deliver a continuing and relatively consistent experience for the many people who love them.
Additionally, a series like this is inevitably going to be subject to feature creep and it would be functionally impossible for them to maintain every new feature, while also including new features in every game. I'm sure I'll get called an apologist for this, but the fact of the matter is people love these games, they don't need to "change", and it is inevitable that not all features will be included forever.
I'm by no means saying you can't be disappointed, I have my own issues with Pokemon games old and new, but to say the lack scope is utterly absurd.