To answer the original question, no I don't think you can call it racism, but it is xenophobic and prejudicial behaviour.
I'm Welsh married to a Scot, living in England where our children were born.
I absolutely find the intolerance towards the English very offensive.
Both DH and I have both witnessed in our respective home nations, really quite awful behaviour when visiting family.
It has to be said it happens when our children speak first and the assumption is the whole family is English.
The U-turn when either DH or myself speak as a follow up is often quite remarkable.
It makes me really sad if I'm honest.
I want the children to feel relaxed and happy in the nations where DH and I were born. I want them to enjoy visiting those places and "feel/belong" to that part of their heritage.
However, we've witness first hand that the situation is getting worse as time goes on.
I fully appreciate the pressures second home ownership and AirB&B can put on a community and my relatives in Wales have certainly been subject to this.
It is damaging on so many levels - raising house prices beyond local reach, reducing trade for local hoteliers/B&B owners, leaving villages decimated out of season and making some places undesirable to live because it's impossible to function normally when next door to a holiday home where 2am noises booze laden hot tub sessions happen every night and you need to put the children to bed/get up for work.
This absolutely needs clamping down on big time.
All that said you can't blame "the English" such as my children for wrongs done hundreds of years ago. Or for policies in Westminster.
It has sadly imho become socially acceptable to exhibit extremely prejudicial behaviour towards the English and no, I don't think it's acceptable.