How bad it would be for apple? Any virus what can infect iphones, even if its not jailbreaked?

How bad it would be for apple? Any virus what can infect iphones, even if its not jailbreaked?
also patching it would make any iphone work very slow or kill iphone completely.
and it this security would be hardware based.
so how bad it would be for apple, if nofting that actually happened?

It'd be impossible for one thing.

To get the virus, one would have to download an infected app, but the only way to officially download apps is through Apple's iTunes store.

Any app that wants to be sold through Apple has to go through a bunch of external and internal testing. You aren't going to slip a destructive app through Apple.