I don't agree with the people who bash Fallout 4, but it's true that it does have annoyances not present in the previous title...but every title in the series has that. The dialog system was changed in a very unpopular way -- one couldn't see fully what one's responses were prior to choosing them from the response menu, and the only effect of most dialog was to alter one's relationship with one's current companion. The plot interactions based on the player's actions were much less complicated than in Fallout: New Vegas. And at very late game, high player levels, the enemies turn into bullet sponges due to how the game scales. Doesn't feel as satisfying to shoot something. And the "legendary" item and enemy system was transplanted from the Elder Scrolls series, and at least to me, feels a bit weird in a non-swords-and-sorcery context thematically. I personally preferred the American Southwest setting where Fallout, Fallout 2, and Fallout: New Vegas took place over the eastern US, where Fallout 3, Fallout 4, and Fallout 76 took place. I liked the characters in Fallout: New Vegas more. Fallout 4 felt something like a bunch of mini-stories glommed together, less thematically-consistent than Fallout: New Vegas.

But Fallout 4 also has some things that I really like about it. It had base-building, and -- while it still had its share of bugs -- was considerably less-buggy than Fallout: New Vegas -- which was godawful from a stability standpoint and loaded and saved increasingly-agonizingly-slowly the further one got into a game, and was prone to having the player fall through the map. On a given run, some sort of quest tended to break for me in Fallout: New Vegas. The "skill" system that had been present in the series up until Fallout 4 entirely went away, leaving the stat and perk systems, and I think that that was a good move -- the small increases to skills felt grindy, where each increase didn't produce a meaningful impact. The combat aspect is generally-considered to be better. New Vegas had solid DLC, but I'd rank Fallout 4's DLC more-highly. Fallout 4 is a little more open in terms of the order in which you play the game -- yeah, they're all technically open-world, but Fallout: New Vegas tries hard to nudge you in at least some general, rough directions. Fallout 4 is closer to just letting someone go and adventure where they want, in whatever order they want. The scale was bigger, had more people running around, felt a little closer to being a "real world" environment. The game was prettier, partly due to just being a newer game -- Fallout: New Vegas suffered significantly more from pop-up and limited draw distances, I'd say.

I think that at the time of their release, either Fallout: New Vegas or maybe Fallout were best, just in terms of how they compared to other things at the time.

If I were going to recommend that someone play just one Fallout game in 2024, though, it'd be Fallout 4, as the other games are getting pretty long in the tooth. Also, much more modding work has been done for Fallout 4 (though there are some impressive mods for earlier entries, like Tale of Two Wastelands, which basically imports Fallout 3 into Fallout: New Vegas and makes them one game).