Yes they were used by some, now they’re used by (almost) all...
and yes both are laden with man-made chemicals
While I understand your point, my experience doesn't match what you suggest. The use of phosphates had become pretty universal prior major TV exposure. What was going on in California, I have no idea. From NEBS-land down to Texas phosphates were a player.
Pitmasters brought more people to comp BBQ, but the internet, and classes, have had a much greater impact on what's turned in.
I've judged about 25 contests but it's taken me 10 years. This year I'm joining a team to see what it's like on the other side of the fence. Because of how competitions have evolved during my involvement, I don't see much reversal in the current trends, or if there were changes they would take a long time. That said, one thing I've discussed a few times with cooks and two organizers I know was how competition BBQ would be different if the contest supplied all of the meats. Would the playing field be more equal, or would the top teams still rise to the top because they have refined their cooking skills?
For lower cost and most likely an increase in the "fun factor", backyard, non-sanctioned or single meat events (like a rib or steak cook-off) can be a lot of fun, but there can be issues with judging and of course prize money is reduced.... some just give out trophies. Also on the "fun" side of cooking contests are the chuckwagon or cowboy cooking events, chili contests etc.... so there are a few options that take less money and less equipment. I think the reason some competitions have a Kids-Q contest, or a "mystery meat" or "dessert" category is to get some family involvement or something different to increase the fun factor.
Sterling Ball has his Guinea Pig concept. Initially I thought top teams would be reluctant to give up a potential advantage in meat selection, but many continue to cook those contests. After some thought, I decided that meat randomly provided to all teams actually favors the better cook. In the event that they receive a lesser cut they are usually much better prepared to deal with it than a new/average team. Rather than leveling the playing field, I think it actually tilts it slightly to favor the better cooks.