Broken already (Re: Amazed that this stuff is so difficult)
One sprocket hole, heck even one frame, would add/subtract at most 50 milliseconds of latency. Yeah, the guys who claim to be able to assess the amount of oxygen left in your cables might object, but real people in the real world would not notice.
What I, and the comment you are replying to, are talking about is where the audio gets out of sync with the video by multiple seconds, making the experience indeed akin to watching a badly dubbed film.
The issue is not likely to be addressed by anything a WiFi standard can help, as the content is broken well before the connection from your receiver to your TV/speakers. I first noticed it during the run-up to the digital TV transition, when my totally analog TV, receiving off the air via an antenna, started exhibiting this behavior. A little digging found that the networks had started doing all-digital feeds to the local stations, so even though there was no way for latency warts to appear between the analog transmitter and my TV, it was too late at that part of the chain.
Synchronized sound was "born" in the 1920, and "died" in about the 1990 (at least in the U.S.A). So, three score and ten applies to technology as well as people (see also the years between the mid 1950s and late 1990s, when a radio didn't need to "warm up" _or_ "boot up" :-)
Maybe in another 30 years or so, home wireless boxes will be so full of deep packet inspection and neural networks (for "crime fighting") there will be a bit of extra capacity to fix this sort of thing. I'll be too dead to care.