Of course, when the English do it the Scots and Welsh care a lot. Which is understandable, but it's unreasonable to expect non-natives to understand domestic squabbles.
I was entirely unaware until this week there was even an issue about The Netherlands/Holland and I bet that fewer than 0.1% of people here know even that much. It's not a case of not caring, it's a simple case of not knowing.
As for Dutch being a term of abuse, that may well be, but it's lost in mists of time. I certainly wasn't aware of that connotation and I doubt that few are. keep to the Fen Causeway
Yes, they'll call the english on it, practically every time and with good reason. But, as I said, it is largely a domestic squabble and shouldn't concern non-natives. keep to the Fen Causeway