So you're saying you're worried about apple pushing a malicious iOS update because they want your fingerprint?

If yes, this feels utterly nonsensical. They would be able to grab your fingerprint from the sensor anyway, whether you are actively using it or not...

Alternatively you might be spreading some weird conspiracy theory that instead of securely storing a "hash" of the fingerprint on a HSM, current touchid implementations are secretly sharing your fingerprints with Apple.

That's not really any less nonsensical.

It's not your fingerprint that's the issue, it's the data that represents your fingerprint. If that data gets compromised then it's nigh impossible to change your fingerprint. However, I believe there are ways to make this very significantly difficult, and I believe Apple has achieved this level of difficulty by placing the fingerprint data in the secure enclave.