This question Why did Acorn use the 6502? is receiving close votes!
I found this surprising, since my very similar question, Why did Sinclair choose the Z80 for its range of home computers?, was well-received and I don't recall it attracting close-votes.
Is there anything different enough about these questions that one may be on-topic and the other not? Or do we need to reach a consensus?
First of all, while Retrocomputing hasn't changed all that much, the Sinclair Z80 question was in 2016. Attitudes about these types of questions may have changed a bit in 8 years.
I think the key is "Opinion based", which is the stated Close reason - 3 votes so far (not from me, I like this kind of question). The question, as is often the case with Retrocomputing, is whether it is possible to find any documented information and/or first-hand accounts. Both are hard to find for computers designed 45+ years ago. The documentation is often not on the internet. There are computer magazines, users manuals and other paper scanned and available on the internet from that era, but these types of decisions are unlikely (not impossible) to have been publicly reported in a form that would be scanned and easily searchable today. And unfortunately many of the pioneers with first-hand knowledge are no longer with us, though I have been pleasantly surprised to see occasional messages from people involved in the industry at the time or their children or other people who knew them.
Which ends up leaving opinion rather than documented fact for a lot of things. I recently gave my answer as to the history of floppy disk write protect notches. Can I prove it is correct? No. But my logic says it is probably correct, and someone may be able to answer these "CPU choice" questions in a similar way.
