It's very sad but these things happen. Display flying will always involve some risk, especially in vintage types. The pilots & anyone involved with warbirds are perfectly well aware of this & accept it as part of the job.

I thinks it's too easy to become over-sentimental about the actual aircraft. No matter how rare a plane might be, it's a piece of machinery which can be rebuilt if the desire & finances are available. This cannot be said for human life.