There are two things old Pokémon fans remember about playing Red and Blue for the first time: Their chosen starter (Charmander 5eva) and what a big honkin' jerk their "rival" is. Regardless of whether you call him "Blue" or "Gary" (as per the Pokémon anime), you can count on him to choose whichever starter Pokémon has an advantage over yours. Don't bother restarting the game; he does it every time.
But outside of competing directly with Giovanni's mean-tempered son in Pokémon Gold and Silver, players haven't come across too many "mean" rivals since Pokémon's earliest days. Whatever happened to those punchable faces and grade-school insults ("Smell ya later!")?
According to Pokémon director Junichi Masuda, better graphics from one Pokémon generation to the next is one reason for the change; improved visuals make it easier to give people different personalities. "We were just limited in what we could express with the pixel graphics [in the early days]," Masuda told GameSpot in an interview. "There's not much that you can do with that kind of little sprite on the screen, so we worked harder to characterize them through dialogue and give them certain personalities."
"Another thing, just my own personal take, is that it feels that people with [jerk] personalities these days are just not as accepted by players as they were back then," Masuda added.
Pokémon rivals started becoming much more pleasant as far back as Pokémon Ruby and Sapphire for the Game Boy Advance. I personally find sweet little Wally much more likable and interesting than the one-dimensional rivals of Pokémon Red, Blue, Gold, and Silver. In fact, modern Pokémon games have changed up what "rival" means. The foul-tempered Gladion is sort of your rival in Pokémon Sun and Moon, but he eventually becomes an ally—and you discover he has some very good reasons for being prickly. I suppose Hau counts as your direct rival, and he's sunnier than a summer's day on his island home. That doesn't mean his agreeable mood is infinite, though.
If you miss having Pokémon rivals worthy of being kicked in the shins, don't worry: You can re-visit Kanto on the Nintendo Switch very soon. Check out our Pokémon Let's Go Pikachu and Let's Go Eevee guides.