Earlier quoted context omitted.
I haven't actually seen any travel warnings published by other nation states (yet). Do you have a source?
"So far, Portugal, Norway, Denmark, Finland, Ireland, Germany, France and the U.K. have all issued new travel guidance for those wishing to travel to the U.S." https://www.newsweek.com/portugal-issues-travel-warning-us-2...
Last I checked, Germany's advice was similar (i.e., not a general warning); and from the article, it doesn't look like Portugal's advice is a Travel Warning either. There's a difference between making information available, and providing warnings.