I would prefer Twitter error on the side of more labels for increased context than fewer, just because others haven't gotten it yet does not mean they won't.
I agree it's fair for them to protest, just seems a bit hypocritical to post the GP quote on your website and then complain when you get labelled for alignment. Quitting just seems a childish response on NPR's part. How many people and orgs do they label and make claims about?