Agreed with the concept and prediction, @wouter-v.
While I admit hardware is not my field and I thus may be mixing up things here: doesn’t Apple already have a secure enclave on its more recent chips (last 2 mobile generations)?
I know, Spectre.
Additionally, Apple isn’t likely to open that enclave to developers, but it would be the proof, without pudding for now, that your prediction is a sure future.
Not sure if the secure enclave would be able to generate a private key right now. I expect Android to take the lead soon..., Huawei, Samsung, Oppo etc. Interesting times..