The other reason I don't think this is going to happen: That small group of owners, to have standing, will have to claim that they are harmed by the changes. In general, a garden variety owner will be
helped by the changes--lower supply of rentals arguably means both more booking availability and higher rental rates for the rentals that are "allowed."
To claim one is harmed by this, I suspect that one would have to claim that they are doing those things
without admitting that they are acting "commercially"--because if they admit the latter, they are admitting they are in violation of even the earliest vague language. That's going to be tricky, though not impossible. I don't see many garden-variety owners putting themselves in Disney's crosshairs on this out of the goodness of their hearts, and those who actually have a side hustle rental business are going to be keeping their heads as low as possible.
In fact, the smart money is going to be headed for the door sooner rather than later, because they can hear the music has stopped.
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Edited to add: It's not really more booking availability, so much as it is better
high value booking availability, where value is measured by how much you save over Disney's rental prices per point. Those high value rentals are the obvious and disproportionate targets of the more-than-casual renter.