It's more than useful. It's correct. (-:
There's a behavioural contract for process 1 on #Linux, and shells do not fulfil it. They don't handle things that process 1 has to handle, and they conversely do things that process 1 should never do.
Ironically, sh as process 1 is nowhere near a truly minimal approach. With two significant exceptions, one of which was a BSD project that failed, there is no proper process 1 program that does parsing in process 1, for starters.