I mean, not directly. The ad team didn't get a team together and say "make a protocol that will get our ads to the browser quicker", it's likely a team made to "make the internet faster by solving problems with TCP", and it just happens that A. they're funded by ads and B. this speedup also happens to work in favor of ad delivery. Same for the other parts of the internet, like dynamic content [chrome, JS] and OS speed [android], they're making the entire internet faster which ends up including how fast they can push an ad.