I agree that there is a lot more risk on the renter side than the owner side. If the owner gets paid with Zelle, or Paypal F&F (which are "safe" options if you want to eliminate chargeback scams as an owner) then what's the risk for the owner?
On the other hand, as pointed out by earlier in the thread, the owner maintains complete control of the reservation. What's stopping an "owner" with malevolent intentions to cancel a reservation after getting paid? I do agree that the vast majority of owners are decent people (in fact, I used "owner" above because scammers are likely not actual owners!) but when scams do happen, renters rightfully complain online and other maybe other renters think twice or are a lot more careful when renting.
A renter should definitely do certain things to protect themselves like asking for a rental contract, verifying ownership with the county, talking to the owner via phone, avoiding a large deposit upfront, confirming reservation in the Disney app before the final payment, and checking that the reservation doesn't disappear from
MDE after the transaction is complete. A contract is important not just to lay out the terms, but also for things like payment timelines, cancelation policy etc.