Unfortunately the British flag (union jack) and the English one (st George's cross) are viewed as frightening in many places outside England.
I'm Irish (Southern Irish, Republic) , not very political but I'd never buy a product with a union jack on it. I have become aware though that probably the marketing departments of Tesco and Marks and Spencer are oblivious to that. I then realised, perhaps the wider British population are oblivious to how their flags are perceived?
I associate those flags with racist, thuggy, British Empire types and I know most other Irish people do too. It's something that rings an alarm bell on your head when you see it. I equate it with trouble and danger.
By watching British tv shows I've come to realise it doesn't necessarily mean that in every context. I watch 'Escape to the Chateau' and see Dick and Angel have large union jacks in their hallway and one of their suites. I think it's there in that case as a sort of vintage accessory but I'd still never stay in that suite, no more that I would in a suite with a swastika or confederate flag.
I've also seen interiors shows where people would have union jack cushions and I'd internally wince. As well as the association when the far right and war it's very aggressively graphic, on your face, can't miss it.
So I suppose it's in the eye of the beholder, but it'll always be a scary symbol to me.