You could be right but let me tell you that the wifi chips are not identical on all iPhone models. The chip part number is different in each generation. That is why iOS7 is having an issue with major 4S devices. There are videos on youtube showing users on a completely functional iOS 7.0.3 4S device... but as soon as it is updated to iOS 7.0.4, the wifi is greyed out!
The only logical conclusion is that 7.0.4 is buggy with the wifi chip model on the 4S. I know around 10-12 people at work with a 4S device... all of them... Yes.. all of them have this issue. It was working fine on 7.0.1/7.0.3 (didn't see anyone using 7.0.2). As soon as they updated to 7.0.4... BOOM! wifi greyed out.
Now this cannot be a coincidence... since all of them didn't purchase it from the same retail store or at the same time (The purchases of the 4S devices varied from 3 to 6 to 12 month gap). There were a few who were covered under warranty and got a refurb 4S and were instructed NOT to update to the latest firmware by the Apple "geniuses". Hmmm.... now I wonder why an Apple rep would say that?! The answer to that is obvious... incompatible hardware on the 4S gen.
I won't say it's a hardware issue. The wifi chip hasn't taken damage either. Some user on Youtube stated a good point, that the 7.0.4 firmware might have recorded the wifi chip's temperature wrong and forced it to shut down. This might get fixed with 7.1. But we'll just have to wait and see.
I haven't spotted a single 4S device on 7.0.4 with a working wifi (unless they have tied the heating method which works as a temporary fix but I wouldn't suggest doing that).
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