The difference is that it is trivial to determine whether they’re selling something that works, which would be the thing to hide in the event of fraud.

Or the fraud is purely financial, in which case it wouldn’t be obvious to an engineer anyway because that level of siloing is normal.

Just like wearing turtlenecks won’t make you Steve Jobs, maintaining a corporate culture of total secrecy will not make you Apple.

Except Apple delivers.

No. For starters we have plenty of evidence that Apple is not a scam. Secondly "one too many “need to know basis” explanations and it’s time to start asking some hard questions" is a pretty clear qualifier. The difference between protecting legitimate secrets and keeping things secret that aren't really secrets anywhere else and have no value as secrets accept to deceive is pretty clear.