And I am part of WG14 (so a hapless goldbrick). The reason VLA were made optional to make implementing C easier, as C99 was not adopted quickly. Although the reason for the slow adoption were others. MSVC did not really support C at all at C99 time because they thought everyone should transition to C++. Only very recently C support catched up in MSVC.
The people at WG14, Google and Microsoft (VLAs are one of few C99 features not ever coming to MSVC) think otherwise.
So you're basically saying they are wrong.