I once had a coworker that used a mini PC instead of a laptop for work. Being lighter, and more powerful worked well for him.
My understanding is that each brand will contract out the design and manufacturing, with potentially totally different factories and people involved. So the same brand will have models that are built totally differently, in terms of quality and ethics. This happens from the cheapest no name products to big western brands. Make sure to check reviews for the specific model, and not blanket trust one brand to be ‘good’. Notebook check and robtech on youtube do mini PC reviews.
I feel you on the ethics side, and unfortunately it’s pretty difficult to ever avoid. You can try buying second hand, at least save something from landfill and get a bargain.
Another aspect is the social graph. It’s targeted for normies to easily switch to.
https://signal.org/blog/private-contact-discovery/
By using phone numbers, you can message your friends without needing to have them all register usernames and tell them to you. It also means Signal doesn’t need to keep a copy of your contact list on their servers, everyone has their local contact list.
This means private messages for loads of people, their goal.
It’s a bit backwards, since your account is your phone number, the agency would be asking “give us everything you have from this number”. They’ve already IDed you at that point.