IMO it comes down to the actual clients and work. Like you said, there are legit reasons for digital forensics.
I assume in your country that there is some judicial process, including challenges and appeals, involved in searches and that those phones are allegedly being used in specific, articulated crimes. If that is the case then I think there’s justification for trying to get into the phone. However if that judicial process is absent or a sham, there are no crimes being articulated beyond hand-waving like “terrorism” or “national security”, or the entire apparatus is rotten to the core, then it becomes immoral.
I know people who have had similar jobs and when a bad job comes down they refuse. So far, they haven’t been fired, but they were willing to be fired. If you were cracking the phones of child molesters and human traffickers then you’re doing good work. If it’s people protesting climate change you’d have an ethical duty to refuse, and be prepared to walk.
I interacted with devs at several Zenimax studios and watching all the employees in other countries take long vacations, generous parental leave, etc. really threw into sharp relief how fucked the USA is. And Zenimax USA benefits were considered good by USA standards, but they were so obviously nothing compared to countries with worker protection enshrined in law. Surprise, despite all that time off, many of those international employees were still extremely valuable.
Across foreign and domestic employees, Id Software in particular seemed lean, talented, and just generally switched on. One of the best experiences of my career. Arkane Lyon, too. I was dumbfounded at the layoffs. It’s like Microsoft excised the most creative and productive parts of the company on purpose.