Yep, it may come from that, or maybe as it often happens someone wrote a best practice in the coding style rules, something reasonable like "try to avoid returning from the middle of a function".
People didn't understand that, too vague, hard to enforce. Someone else decided to make it clearer, "try to avoid multiple returns inside a function".
Then someone else comes and decides to tidy up the coding style document, put it in imperative form: "All functions should have a single return statement".
Give it a couple of years, people forgot why the advice was there in the first place and now they just blindly apply an insane rule, teach that to new hires and enforce it in reviews. All functions now look like big arrows and every once in a while the max line length rule has to be relaxed a little to allow for all those levels of indent.
Maybe that's how it entered MISRA-C in the first place.
I'd argue that in languages with manual resource management, you should be very careful how you return in the middle. Say you allocate something, or initialize communications with a device before a loop begins. In the middle of the loop, you find your result early and want to return it.
But your "return" should also have all deallocations performed! Also if you open communications to some external devices which tend to be notoriously stateful, you need to bring them back to a usable state by either completing commands sent so far, or resetting them, or whatever is needed.
If there is nothing analogous to "defer" statements or "finally" clauses, you will be in a world of pain if you sprinkle return statements without paying attention to all details.
Thus I can see a point of such a rule being in MISRA-C or something like it. Guess it's better to enforce an easily checkable rule (prone to birthing monsters) than educate all people properly.
Notice I purposedly used "reasonable" and "in the middle of a function". I know where this rule comes from. It's how it evolved into a blind prescription that is a problem.
People didn't understand that, too vague, hard to enforce. Someone else decided to make it clearer, "try to avoid multiple returns inside a function".
Then someone else comes and decides to tidy up the coding style document, put it in imperative form: "All functions should have a single return statement".
Give it a couple of years, people forgot why the advice was there in the first place and now they just blindly apply an insane rule, teach that to new hires and enforce it in reviews. All functions now look like big arrows and every once in a while the max line length rule has to be relaxed a little to allow for all those levels of indent.
Maybe that's how it entered MISRA-C in the first place.