Iwata, you are missed. The game that the Nintendo president at the time personally helped to shape and improve left an indelible mark. I understand that the second generation of Pokémon, in terms of the creatures, is considered one of the weakest. However, the fact that this game included two regions and demonstrated the passage of time in the previous region is something that should be explored again.
Since that era, Game Freak's inexperience in programming has been noticeable, a problem that unfortunately persists to this day. The absence of someone like Iwata, who could fine-tune and improve the games, significantly harms Game Freak.

Played up through the 7th badge (these games go by quick with 10x speedup!) I was actually surprised at my bad reaction to G/S: in my childhood mind, these were the best two games. Likewise, I was surprised how good R/B felt.

To my surprise, G/S feel a bit flat. The locations and landmarks feel more touristy than anything: rather than the way that R/B's world was a little denser and intertwined and felt like it was drawing on some kind of Japanese childhood/adulthood, G/S's map feels a bit more arbitrary with various 'tourist destinations' dropped in here and there, weirdly intertwined with Team Rocket and Rival stuff, scouring the maps for missed HMs. I appreciate the effort to tie real world history to the game, but it feels a bit dropped in - the mythology of pokemon themselves don't feel that tied to the systems - being a kid and getting badges, fighting pokemon.

The Radio, night/day, new balls, phone calls, etc - these are all new and sort of cute but they also don't feel super relevant to the main game based on what they amount to.

Overall there are still some nice moments: I liked the underground walkway with trainer fights this time! The way the northern/northwestern reaches of the map seem more steeped in forests and caves is an interesting contrast. Seeing regions guarded for cultural reasons (Dragon's Den guarded if you don't tame dragons, Tin Tower if you're missing a badge) - these border on interesting, but they still feel detached from the main character - a little kid who for some reason ends up catching Gods and taking down terrorists.

You can really see the pokemon formula start to take shape here: new pokemon, a new villain group, another kid who for some reason ascends to divinity-level strength against a world which contradictory..ly tries to stay grounded. A world obviously inspired by some real place, but that canonically refuses to be linked to that real place.

I have no doubt that some of the later games manage to balance the battles, complexity, and story better - but none of those things are really what made Red/Blue so interesting to begin with.