Definitely less common in the USA. I'm with USAA and Prudential for different types of insurance and neither offer it. I don't know about Allstate or State Farm.

Travel companies try to push it, usually with insurance firms that I have never had any relationship with and haven't ever researched. It's never clear to me how/where the insurance company is located/incorporated, regulated, or what the venue would be for any dispute.

Residents of bigger states, especially places like NY that have a pretty active consumer-protection function in the AG's office, may have clearer published guidelines on how to research and buy travel insurance from reputable firms. Just not a thing I've ever looked too far into.

I remember when I lived in the UK, some of their national, trusted insurance companies offered it. Most of my friends bought an annual policy, which was pretty affordable.