When they went after the AP holders that were doing the personal tours and using
DAS to help families skip the line Disney knew who to go after as they had already been tracking them. I believe they received a cease and desist letter, then if they did not stop their park tickets were flagged and they were denied entry and issued a no trespassing order for WDW property. If memory serves me correctly one was a DVC owner. I believe he is allowed to go to his property and use his points but he is not supposed to go on other Disney property. I have seen his wife posting during his banning and the only place he is seen in images now is at the DVC resort he was at, which may have been their home resort.
I know this is different in a lot of ways but I do think if Disney thinks they are loosing money because of this they will invest the resources to stop those they believe are at fault.
Also there was a change to recent timeshare law in Flordia regarding badly behaving guests and the timeshare company having the right to deny them access to their purchased timeshare property. I do not remember all the details of the law but it gave time share companies a lot more options for what is deemed a badly behaving guests/owner. It would be interesting to see what the laws definition of badly behaving is and if Disney could make a case for commercial renters behaving badley.
Either way Disney will go after who they view as impacting their bottom line. Whether it is DVC sales due to renting or moderate/deluxe resort bookings due to renting only DIsney really knows but either way I do believe they are more focused on that then any negative consequences for current owners. Plus as we can see from all these debates owners are spread all over the place regarding what they view as commercial renting, spec renting and what is and is not okay. As a result no matter what Disney does there will be negative feedback and positive feedback. So more reason for Disney to do what they view as best interest for their bottom line, be it continue to ignore renting or become more aggressive.