Not really moot. I do C++ on embedded processors with as little as 32kB of program space. Using a single exception means your code will not fit. My general rule of thumb to use full-fledged C++ is a processor with at least 256kB of program space.

Here's a comment of mine from a previous discussion: https://news.ycombinator.com/item?id=11706840

Not in the bare-metal environment. You may not have the memory to use one. In such a case, the increase to use two is irrelevant.