It is a proof that we can get what we need to done in a language that is not Turing complete. The hope would be that there is some sweet spot we can find where

It is a proof that we can get what we need to done in a language that is not Turing complete. The hope would be that there is some sweet spot we can find wherein we can say things that are dramatically more useful than "it will finish inside 2^(2^100) steps" without impacting usability tremendously more than "it won't use more than a kebibyte of memory" - which is already enough to defang the theoretical objection.