This, slightly further down in the comments, along with the idea of Kernighan's Lever, gets to the problem with that sort of flexing:
"This implies that programmers exist in isolation. Most of the code I read was not written by me. If the subset of the language that I stick to is a completely disjoint subset to the one a collaborator sticks to, we can’t review each others’ code. If I jump into a new project and it’s using a distinct subset of the language to the one 1/2