True, but it's not like the Nats didn't vet the issue or that insurance was readily available.
The insurers knew that Strasburg had a lot of miles on his arm, and an injury history, including TJ surgery. So, the word is that the cost of the insurance was close to 40% of the contract amount, and included all sorts of outs for the insurance company. Even though Strasburg threw few innings, he did pitch in 2020, 2021 and 2022; so, who knows what the insurance company would claim the amount that should be paid to the Nats. Also, with Strasburg retiring with years left on the contract, there may be a settlement reducing the amount to be paid over the final years of the deal. Not sure insurance would have put the Nats in that much of a better position given the cost and that Strasburg has retired.
Bottom line is that it was a terrible contract to a pitcher with a fragile arm, and an injury history. Even so, the Nats would have never won the W-S without him, he was the MVP, and they rewarded him for past performance rather than paying Stras on expected future results.