While I have been using Linux since 1996 or so, and do have quite an opinionated workflow, I never could agree with this kind of ultraconservative approach to things. History never stops. Things change. Linux changes. Not every day, not every month, but every couple of years something has to go. And that's ok.
Same here, I do think UNIX did some stuff right, but also did lots of stuff wrong (otherwise The UNIX-HATERS Handbook wouldn't even be a thing), and while the command line is useful for some tasks (which can also be done on a scripting language REPL), it is hardly something to settle life on. We already have enough UNIX clones, and moved away from TUIs 40 years ago for a reason.
Funnily enough, init.rc used to be on the top of it, as well as all the numerous process/job management gotchas. Systemd + control groups = step forward. Plan9-style fuse-based systems = step forward. Kernel data structures exposed as files = step forward. And so on.
CLI utils will probably have their place like forever, TUIs as well, with the main benefit being the ease of development and staying in the CLI context.