We used to always buy 3rd-party travel insurance (and fortunately never had to use it) but with trying to get back into cruising post-pandemic have gone with Princess, mainly for the Cancel for any Reason. We're Platinum, so we get the 100% back. We recently had to use it when we decided to cancel after final payment - we received our FCCs within a couple of days, as well as the amount refunded directly to our Credit Card. I also always book refundable airline tickets -- either cash or credits.
Also, with the Princess insurance, you don't have to pay it until final payment (although you may need to check the Pre-existing Conditions section), so if you cancel before then, you're not out the insurance cost. Cancelling after payment, we of course, didn't get it back but wouldn't have with other insurance either.