Because you buy Fallout to ape anything having to do with sci fi and pop culture and horror and then throw it in the game. Then you get fallout 3 and 4.
Yeah...but they did that both with Fallout 1 and 2, way more in 2,, but if you think that meta humor is just in the random encounters and don't count, you've been away from Fallout 2 for too long. Fallout 1 had a fucking Robinhood ripoff complete with an English accent running the thieves guild in the Hub. Fallout has always been a "rip off" of all kinds of genres and IPs. It had supernatural stuff in it, biological horror, 50s sitcoms.
Fallout is at once very serious story under all it's wacky references and pop culture banter, but that 'creatively bankrupt' stuff is baked into the formula. Fallout as an IP started out as a time travel story involving lasers and dinosaurs. This is why I believe in the poet's truth, that some stories are things "from the gods" and not the visions of their creators, because up to Fallout 4, the series was way more than the sum of it's parts and way more than the gravitas of it's creator's visions. Because Fallout has ALWAYS been conceived of as a shoddy commercial product for nerds who play TTRPGs in their parents basements between the ages of 16 and 23. Thus it's dark, edgy, and meta.
If you don't believe in the spiritual side of storytelling, and I mean the mysticism/new agey level spiritualism and not symbolism, Fallout is and was intellectually worthless from the beginning because how it was designed (a purely commercial product), to whom it was designed for (teenage and college level proto incels, to which I plead the fifth, who were not interested in actually learning anything but just having a good time), and the utter lack of care for how it's tropes were used in relation to how the world actually works (the dead brown nuclear desert).
Fallout as an IP has always been an interactive Saturday Morning Cartoon. That's why Todd 'loved' Fallout and convinced Wager to buy it for him. Todd understands what Fallout is supposed to be, and that Fallout 4 operates on Saturday Morning Cartoon logic is exactly the point, if too on the nose. Tim Cain and Brian Fargo have a slightly more sophisticated technique but the goal and RESEARCH are the same, practically nil. If it weren't, Fallout 1 wouldn't look like Mad Max and Fallout 2 would have looked more like Arcanum, at least outdoors.
Fallout though, is more than it's design philosophy. The first game in particular is so smart I don't think any writer intended it. It looks and sounds like a B 50s/60s sci fi movie the whole way through, and it was probably intended that way, certainly Tim meant it that way with radiation causing ghouls. But with FEV, you find it's not a B movie, it only LOOKS like a B movie. All the mutations are localized and explained through the horrors of that one horrid thing getting nuked and disseminated all over southern California via the air. Suddenly the farce dips away, and the suspension of disbelief pulls to back to an even stronger position than from where it was at the beginning of the story. Once you know the whole story it becomes MORE believable, not less. Because now you have seen a way these hokey cliches might actually happen through more sophisticated means than radiation bad/Hulk smash.
Fallout took something very stupid (that which is set in the real world but actively contradicts how the real world operates is stupid) and made it smart, or smarter depending on your POV.
The problem is not the pop culture references. The problem is the belief that artistic license allows you to engages in solipsism that because the work belongs to you and you can do anything you want with it. Only legally is this true. Morally, intellectually,, spiritually nothing could be further from the truth. Fallout 4's crimes against storytelling stem from this solipsism, and a lack of organic worldbuilding. The Atom Cats are not a bad idea, but they need a rebuilt, functioning Boston to work, and possibly day jobs like they hotrodding construction workers, maybe with only steel plates because the local government doesn't allow most civilians to own the actual power armor plate because it's too rare to be used on anyone but security and trade personnel, kinda like NCR servoless suits but in the opposite way: plenty of frames, but the plating is rare.
The synths are not a bad idea IF their lore is well thought out, it's details researched (like the gut bacteria and such) and firm answers given on their physiology. So challenging the lore in WELL THOUGHT OUT AND RESEARCHED WAYS is not only OK, it's vital. If not for this IP for the ones people would create thereafter. The only solution to bad ideas are better ideas, so instead of dismissing all of Bethesda's crap, engaging with it and seeing how it could work is a productive use of time, particularly for creative types. It's a diagnosis, it's strengthens our critical thinking skills, our actual imagination and not just flights of fancy.