@weaf I bet they said this because they don't have the imagination to understand a story beyond the details they specifically created.
"What happened to X after New Vegas?"
Doesn't matter, it doesn't affect MY story so it's gone.

This is the same reason the Star Wars books were taken out of "canon" the writers were incapable of fitting a greater reality into their understanding.

Everything must be specific and deliberately created by them or it's better off gone. Zero actual imagination.