At my work, I similarly have gotten secure administrative workstations deployed with again, very limited lists of software. These users being compromised has such extreme consequences that one cannot trust any application to run on these computers.
So I can certainly appreciate the need to be very exclusive with the software allowed on a device. Yet I see this exclusivity being rather anti-consumer in practice. iOS is the most secure operating system I've ever seen for the average person, and yet things like adblocking are behind a paywall. Neutering Adblock for the sake of security is considered acceptable. Blocking alternatives to WebKit may reduce the overall attack surface area Apple contends with and it also limits the functionality of the phone since v8 is the de facto standard. Blocking alternatives to the App Store absolutely enhances security while also forcing consumers to pay more. Then you get into things which have nothing to do with security truly, like how you can only make "Music" your default music player on iOS, not Spotify.
I really appreciate what Windows did with "S mode" because it's optional yet provides benefits to consumers in niche situations. I similarly appreciate the enterprise features of Windows to configure a laptop which has limited access to software to enhance security. Apple on the other hand forces the exclusive use of their software to benefit themselves at the expense of their customers. It is unacceptable and I would vote for anybody pledging to outlaw it as monopolistic abuse. Software exclusivity is useful, shoving it down people's throats is abhorrent.