If the USASF were a private company (like the "regular" event producers), that could possibly happen as easily as you seem to have suggested. Someone could just say "hey, we should start up an appeals committee" and it could get done in about an hour.
In a bureaucracy like the USASF, nothing ever happens that easily. You are talking about a proposal being drawn up, it going before review boards of multiple committees (NACCC, Rules, etc). It getting discussed (at length, likely) by each of those committees, then voted upon. If both of those groups approve, then it gets sent to the Board of Directors for approval, who also has the option of discussion, review, etc. They likely will want changes or modifications, so it gets sent back down to each of those committees for review and revision. Then it gets BACK up to the B.O.D., where it could get final approval.
You are lucky if that happens in a single year. It would more likely happen in 2. Then you have to find people willing to sit on that appeals board and decide on the paperwork/procedures/etc. Finding a PAC would probably be no problem. Finding a gym owner willing to sit through potentially hours of paperwork and phone calls AND potentially pissing off another gym owner is not going to be easy. (either way the decision goes, one gym is probably going to be angry about it.) Finding an event producer willing to get involved in a gym vs gym vs athlete dispute is going to be even harder.
THEN, when people think that the hard-and-fast rule about team-hopping to a different Worlds-bound team just became grey instead of black-and-white, more people will try it. I would guess anywhere from 15-30 appeals in the first year. If it works at all like the other appeals systems USASF has had in place before, getting a successful appeal would be INCREDIBLY rare, benefitting at most perhaps 1 or possibly 2 athletes a year. (Meanwhile angering many more.)
My point is not that an appeals process wouldn't be OK in theory. In practice, however, it will take an enormous amount of man-hours to make happen. That much time and effort could be spent on things that benefit more than an athlete or two a year IMO. (safety issues, scoring issues, improving the certification process, etc.)