> I've long used Linux exclusively on laptops/desktops and in the past I've been a Linux/Unix sysadmin but I have no idea how to go about getting a smartphone that runs Linux and works with the major carrier services or how much it would cost.
You aren’t doing enough research or trying hard enough then. PinePhone exists. Raspberry pi+4g modem and accompanying software for SMS/telephony exists. You can find Linux phones with a simple Google search (I find Purism and PinePhone on the first search results page for ‘Linux phone’. Also plenty of Android phones can be rooted. I managed to root every Android phone I owned since I was a teenager with limited technical expertise by following some simple tutorial or another.
It isn’t Apple’s fault that the average person isn’t doing their research or trying hard enough, so why should they be suffering the consequences? This line of thought stems from entitlement. Just because Apple’s solution is so good users feel entitled to other solutions being just as good, and when they aren’t up to par, initiate litigation against Apple for providing such a high quality solution that makes others pale in comparison.