Skyrim wasn't objectively good, but it was well-liked and infinitely moddable.

Fallout 4 had some interesting mechanics, but the story was bad, the in-game radio host was awful, and the engine was a decade old at that point. It was also the game where Bethesda introduced paid mods.

Fallout 76 is a tale of its own. It failed at every conceivable point, including promotion, merchandise, and post-release content.

Starfield is a loading screen simulator with 1700 near-identical planet and a bad story, and is overall so insignificant that I almost forgot to mention it.

Most recently, Fallout 4's newest release broke mod compatibility, the only thing that kept it relevant.

It's fair to say that Bethesda hasn't developed an objectively good game since Oblivion, and that was the game with the horse armors. Plus there are all the games that are owned by Bethesda, but not developed by them. Redfall, Deathloop, and what Id did to Mick Gordon.