[reorder9695]

And how do they prove to me they (and no 3rd party providers) aren't actually storing the data? I simply don't trust companies telling me they won't store something, so to me the only acceptable option is the data to never leave my device.

[ivan_gammel]

If third party does verification with ZKP, you only need to trust that third party. The company that requires verification will not have any data to store.