I once tried to explain to an American about how English/British flags are seen over here, and they really couldn't understand what I was talking about.
There's nothing inherently racist about flying a flag and showing a bit of pride, but for as long as I've been alive, I only ever see racists flying flags (outside of World Cup/Coronation etc). After decades of racists flying flags, I can't help but think that you're a racist if you're flying an England flag. Everybody in England kinda knows this, and the ones who disagree are suspect. It's a shame I suppose. I think if we really wanted to reverse this, IMO, you'd have to do something like fly an England flag but also fly a pride flag on the same pole. It's definitely NOT going to be reversed by a guy who calls himself "Andy Saxon" who used to be part of the English Defence League. That's gonna make it worse.