Judy, I think perhaps you meant to ask if wearing a mask would make you less likely to test positive? I would say the data suggests you wearing a mask would help to test negative.
Generally speaking, I've given up on CDC and State Department Travel levels. I'll look at them to get a broad idea of what's going on. But, for instance, at this moment no one seems to be able to explain why new case numbers have fallen in England right after they lifted their restrictions. Similar decreases also being reported in Spain and Portugal.
And, as others have noted, the US saying other well-vaccinated countries are a concern when our own vaccination and case numbers pale in comparison is a tad hypocritical. There are plenty of ways to see the data and a given country's own view of it's situation and views on foreign tourists to make your own decision on the safety of travel for your own personal situation.