I will stand my ground that Silver is the best rival and best character in all of the games. He had legit progression in terms of how he changes from being a thieving bully kicking you around (because daddy issues, as it turns out--although we only learned this in Gen III) to self-reflecting on his decision as a trainer and how his grudge toward Team Rocket is keeping him from treating his Pokemon correctly. By the time you have rematches with him at Indigo League, he has a Crobat, and he comes to respect you as a trainer.
Although Wally becomes your true rival and escapes his cushioned life to become a trainer, they never tried to give him a character, which is why he's kind forgettable. Now R/S/E shows you that your neighbor is a sore loser who before the seventh gym gives up being a trainer to help their dad in the research field after spending most of the game showing off their "knowledge of Pokemon" under the guise of "being a tutor". It's a real dick move to not get to see the last evolution of their starter, but after pondering on it for over a decade, it's actually kind of unique for Pokemon. It's kind of a harsh reality that some people just
can't cut it as a trainer, and although you crushed your neighbor's dreams (unintentionally), they at least have a back-up plan and still keep their team, and imply they might go back out on the road again (but they never do because it still smarts). They at least still stick to the script in the remake and fixed it by giving you a chance to see the final evolution, but they still showed up a few more times even though they were supposed to be stewing over it back in Littleroot. So either they get over it quickly in the remake, or they were just looking for an excuse to return to being their dad's assistant.
So I think the problem with Game Freak isn't that they're trying too hard to make human characters (N is fantastic, after all), I think they're missing the nuances of characters. Although they're now having cutscenes up the wazoo to show off that they "can do" 3D animation now, it's like what
@rotollo said in that they can't seem to break the "tell, don't show" story-telling that was present in the original games. These new characters won't shut up, and they're not doing anything special or different outside of "LET'S BE FRIENDS, 'KAY???" and following you around everywhere you go. Even
Let's Go Eevee/Pikachu made the rival docile, even though yes, Blue is in the game, but it doesn't mean you still couldn't have a jerkass rival whom you straighten out. (It's implied your rival in FRLG after losing his champion title goes off on his own to self-reflect, so he changes his attitude a bit post-game.)
Maybe we just need to bring back jerkass rivals, or turn your happy-go-lucky rival into your worst nightmare over time because they were always petty little shits who used to get their way.