We had a John Hancock Bronze plan the time my husband had an accident with injury just prior to our cruise a few years ago.  We had to cancel the cruise completely, just 4 or 5 days before we were to sail, so obviously where the cruise would have been nonrefundable. (We were offered a chance to move the cruise booking for a fee, but we didn't know what his recovery time was going to be, so that wasn't a good option for us.)
We were able to recover our cruise fare completely.  Our hotel and airfare were booked in a way we could get credit/points returned, so that wasn't an issue.
The claims process did take a while, and we had to re-submit some of the forms they said they did not receive, but we did eventually get our claim paid.  Note: we had booked through an insurance aggregator that we cannot link to on the DIS.  That company does have a liaison-type person if you need to escalate action.  I think that may have helped in our case.  I'd say it took about 5 months to get our money back. 
Supposedly part of the delay was because this was shortly after cruising re-started, and the insurance companies were still dealing with a lot of pandemic claims. 
I would recommend to keep at least a digital copy of every cruise payment, credit card statements, and if you have a medical issue prior to sailing like we did, keep every bit of documentation you can, and be prepared to fill out a bunch of forms.  (mind you, we also had to fill out work disability forms for a little while, so there was that on top of the travel issues.) 
But all ended up well!