Reading the article I think most people don’t need to worry about upgrading because of this flaw; this would be a very targeted attack. And I can understand not letting the firmware upgrade; I’m pretty sure I’ve seen examples of nation-state hacks for phones that involve attackers installing an “upgraded firmware” that disables security protections to access otherwise secured info. But yeah, cost is definitely a risk with this design.
Yikes. Are you already in a relationship where that could also cause an issue with your S/O? Making them feel jealous/nervous that you would leave for the attractive nurse if you had the opportunity?