Your purchase includes a 12-month Sailfish OS full license subscription

Didn’t expect a Linux phone to be the first subscription based OS. Makes for a total cost of ownership of ~600€ if you keep the device for 5 years. (299+4.99×12×5)

This is called plausibly deniable encryption, though you cannot hide the presence of the system itself.

GrapheneOS has a Duress PIN feature, which wipes your phone if entered.