This is a use case where a decent trip insurance broker which curates, compares, and helps educate customers actually comes in handy. That and travel + insurance experience as one ages so you know what you're looking for.
Carriers aren't always as kind as you've been treated and sometimes people won't be able to use a credit or want the cash back. AirNZ automatically gave me 1 year credit/voucher for a non-refundable ticket for NZ domestic travel when they cancelled the flight while I'm here on the US West Coast. It also currently seems like it has to be used on a single trip and any leftover funds will be forfeited. Had it been an earthquake or volcanic ash which made my destination inhospitable instead of a pandemic? Many credit card and purchased travel insurance policies for trip cancellation would cover that ticket's cancellation fee and non-refundable funds. So again, details. Hitting one of the non-insured trip cancellation clauses which isn't that common won't stop me from evaluating if I should get insurance for the next trip and reading the policy + calling with sample scenarios within the refundable period.
I usually buy trip insurance for medical coverage as it has the potential to be the highest unexpected cost item in my trip. There are travel medical policies available, too, which I've also purchased at times and left the trip cancellation & interruption to credit card benefits if the cost is low and minimal risk. If I want trip cancellation then I usually also purchase Cancel For Any Reason. That's best purchased when you book the initial portion of the trip (cruise, airfare, or hotel) so requires some initial outlay and guesswork on total costs.