Please, it's 2022: anything that is not open source is suspicious of being spyware. We don't even trust our own governments, how on earth are we going to trust any private company (Huawei, Google, Apple, etc.)?
Looking at their 'PC Link' feature, it seems like it can be used without a network as just a mass storage device. If it's airgapped it might be fine. I don't know more in detail though.
So how do you connect to the internet? Have you managed to build and assemble your phone/laptop/computer yourself, using custom chips also designed by you, in order to the stay away from the spyware, or do you care only about Huawei's spyware?
As a person who is totally unaware of anything going with Pinephone and other Linux phones, i'm asking -- are they really unable to make phone calls? Or only in some specific cases?
You can't make phone calls in case you only want open source software. GSM Baseband software is notoriously closed and that's practically enforced by law.