TBH, getting banned from a sub for something that got downvoted there as well just means you said something in the wrong place to the wrong people. That exact same thing can (and does) happen in Lemmy too.
My only permaban in my 10 year Reddit history is for explaining someone making a reference to the MLP cum jar meme, and in hindsight, I did deserve that, even if someone did specifically ask what it meant.
That would require starting a database with the purpose of cataloguing every single part number in every single device that exists, which while technically possible, is rather unfeasible without extensive manufacturer cooperation.
What iFixit is doing is the other way around, they are telling what device a certain part number they carry fits in - as in their example, what Lenovo laptop that specific battery is compatible with. That's a problem multiple orders of magnitude smaller in scope.
In a perfect world though that information would be available in the repair manual and schematic that came with your device, as they usually did a few decades back. Alas, that's something that's never going to happen again because it hurts profit margins.