Just on the ‘Asian’ usage, which is routinely misunderstood by observers from the U.S.
It precedes by many decades the presence of significant numbers of Muslims in the UK. It’s simply the colloquial, especially media shorthand for any of the brown-skinned peoples originating from the Indian sub-Continent. It continues to be used of all such, whether they’re Muslim, Hindu, Sikh, Christian or whatever. It originated from the time when people from the former British India were the only people from the continent of Asia to be seen in any numbers in Britain. It is not, and never has been, a euphemism for Muslim.
Muslims not originating from the Indian sub-Continent aren’t referred to as Asians: though of course the UK Muslim population still originates principally from Pakistan, Bangladesh, and India, along with smaller numbers from parts of East and West Africa, Malaysia and a few from the Middle East. None of those latter groups would be referred to in the British media as ‘Asian’.
I don’t think what you said is completely true. Time and again the BBC refuses to use the word “Muslim” when the perpetrator clearly is so, and says “Asian” instead.