Excuse me? It has everything to do with it. I bought my FTb originally as a manual back-up for my A-1, and it ended up replacing it.
First of all, relax. I am not personally attacking you, and you don't need to throw the "Excuse me?" 'tude simply because someone opens a minor debate with you.
Next,
OP: "Hi, I need a second car for my kid; something similar to a Toyota Corolla, but not as full featured."
You: "I would get a Lexus, because they perform better than a Corolla."
An answer is a Toyota Tercel, not a discussion of the merits of a Lexus over a Toyota.
The question was not, "Which FD body is best for my kid", but, rather, "Which FD body would make a good backup for my kid's A-1." As I said, I agree with your preference. My only FD bodies are early F-1s and FTbs. But my personal preference for one body over another does not answer the OP's question, which was quite specifically stated.
Also, try and find an F-1 or FTb with a lens for $20 to $30...which is about what a
backup should cost these days.
As we all know, there is no better backup camera than a duplicate body. But price does matter; enough so to at least consider cheaper bodies than a duplicate A-1.