I have a similar take on how VR lets you show ads much beyond a rectangular screen, so plausibly commands higher ad revenue if monetised. FB needs to grow the pie bigger: the user growth is flatlining.
Facebook's ad product is shit. They exist because they're a monopoly. Their ad product is shit because they don't understand their clients (advertisers) at all and would rather sink R-n-D into keeping the monopoly thing going instead of figuring out market fit for their product. (In that regard Facebook is exactly like Google.)
t. Worked more than 16 years in ad tech.
Out of curiosity, what don’t they understand about advertisers?