TLDR For non-US context: she’s been nominated for a bunch of Grammies for country music, so she’s presumably talented and people in the US know who she is.
Her performance is being called the new worst of all time (something people have ridiculed Fergie for since her performance in 2018, because they care about national anthems over there) but now she’s in rehab for alcoholism, so that explains it.
Just a side note, I live in the US and neither me nor anyone I know had any idea who she was. I had to look her up after I saw the headlines. Of course, I don’t really listen to ‘country’ so YMMV.
Edit: Also don’t care about the National Anthem but you’re right a lot of people do.
In this video they say that even Rosanne wasn’t as bad 🙈