So you hate kids? Lol
No but honestly, I never played the originals. Are the new games too goofy, or what is it from a writing standpoint that you really dislike from the Bethesda games? You also say it looks like the games took place before the originals, how so? Was the world of the originals even more degraded than what we see in the later games?
I don't think its the gameplay, as I played a little of New Vegas and thought it played pretty bad. So I'm assuming its atmosphere and the characters themselves that are the issue for some...
Part of it is the gameplay. The first two games are turn based cRPGs that were far more open ended. Fallout 3 and 4 fail at all three of their core design pillars. The shooting mechanics in the 3d games are some of the worst I've ever experienced in a triple A release to date. Character builds have next to no bearing on gameplay or role playing opportunities and quest design is incredibly basic.The open worlds in Bethesda's games are a chore to navigate. Then there's also the inconsistent world design itself. In Fallout 1 and 2, very few settlements are built out of prewar buildings. In 3D Fallout, it's almost exclusively prewar buildings (despite it being 300 years after the bombs fell.) The 3d games also have you eat 300 year old food. There are production reasons for this. Fallout 3 was originally supposed to be a prequel and take place 20-30 years after the bombs fell but they changed directions two thirds of the way through development which was a mistake in my opinion. Fallout 1 and 2 had their sillier moments but those moments were typically found in non canon random encounters on the world map and the stuff that was canon made sense for the location (the porn studio in New Reno, The Hubologists etc)
There's also the lore stuff that gives the impression that the folks at Bethesda had never actually played the first two games like Jet being on the east coast, how the Brotherhood of Steel and the enclave are portrayed, synths, etc. Its like they read a wiki and made a list of Fallout buzzwords and threw them in at random places in script.
Fallouts original creator Tim Cain said they went with an Ink Spots song in Fallout 1 as a tribute to his father. They didn't go with "I don't want to set the world on fire" because he felt it was too on the nose. I think it's the perfect metaphor for the design philosophy differences from Interplay and Bethesda.
New Vegas is the unholy combination of both, it fails at being an FPS and an open world game but core role playing experience is there and quest design is substantially better. If someone turned New Vegas into a proper cRPG, I'd probably never touch the original game again. Hell, New Vegas even makes jokes about Fallout 3s dumber story elements.
As far as the show goes, I think they made the best decision by going back to west coast because the lore is more consistent and you don't have to deal with the ridiculous factions on east coast. I'll give the show a 10/10 right now if synths don't show up at all. They probably will but I've made peace with that.