What actually defines Fallout canon, and why should it be Bethesda?

I grew up playing FO2 (never got past the SF Spleen bug). I later played FO, then way later FO3, FO4, and sadly after 4, FO:NV. (That is, I wish I'd found FO:NV which might have redeemed FO3 existence.)
I've since encountered what is "canon" and what is not, and I want to know how Bethesda's later stuff determines what is actual FO canon?
I ask for a number of reasons, based on https://fallout.fandom.com/wiki/Timeline, but specifically ask about the dates listed as non-canon that one would still encounter in-game for FO and FO2. Many options are in those games that the Vault Dweller/Chosen One (etc) actually triggers or participates in are listed as non-canon. So while I am okay with enjoying the possibilities in Chris Avellone's Fallout Bible, how is "canon" officially determined?

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Why does Bethesda own Fallout?

Bethesda Softworks owns the rights to the Fallout intellectual property. After acquiring it, Bethesda licensed the rights to make a massively multiplayer online role-playing game (MMORPG) version of Fallout to Interplay....Main series.1997Fallout20172018Fallout 7620 more rows

Does Fallout have a canon?

For us, it's always... for us, canon always starts with what is in the games. And so... it's what is in Fallout 1, Fallout 2... even some of like, Fallout Tactics is- there's some stuff from canon from Fallout Tactics as well. And our Fallout games.

Is the f76 a cannon?

Characteristics. The Broadsider is a naval cannon which has been fitted to a metal chassis. The powder is fired electronically with a button rather than via fuse. The whole cannon swivels upward to load cannonballs through the muzzle.

Is Fallout 3 non canon?

No it's not canon. Its "story" is completely irrelevant to the core region, thus it is little more than fanfiction and can be happily ignored.

Bethesda NEVER Understood Fallout

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