You said the OP shouldn't use LL-01 FE in his engine and the dealer put the wrong oil by using it. Should people follow recommendations by an accountant like you with minimal technical and scientific understanding of engine oil
instead of following the recommendations in their owner's manuals?
Engines have many versions. You don't know if the newer versions have better oil cooling among other things. Most new BMW, Audi, Jaguar, etc. engines spec 0W-20, and there is engineering research and development going into that.
The oils I suggested are
very similar to the their BMW OEM counterparts. Castrol and Mobil 1 are
not "Walmart oils." You can shout as much as you want that BMW OEM oil is better than Mobil 1, but you have zero backing
and zero understanding of it.
Driving a BMW makes you as much an oil expert as using an iPhone makes you an electronics expert.
Stick to accounting.
