There is one finding that annoys me: “One of the most stark findings from from NatCen’s 31st annual report on public attitudes is that 95% of respondents now think it is important to speak English in order to be considered British. That’s a sharp jump from 86% the last time the question was asked in 2003.” I’ve not seen the questions in the survey, so I can’t interpret this finding, and it is only reported that it is important, not obligatory, but on the face of it could have ramifications for Welsh, Scots, Gaelic, Cornish and Manx speakers, and the status of their languages in the public perception. If the reported shift in attitude is caused in part by UKIP, then no thanks to them, and some awareness raising may be required.
I think this is probably connected to UKIP and EU issues, as you surmise. I also expect most of the people answering the question were thinking about people like Muslims, etc., when responding and probably wouldn’t have given a thought to the original British languages, somewhat ironic, I know. This is a hot issue at the moment because of the lurking EU referendum.