What was the figure for other groups - Sikhs, Hindus, Jews, Catholics, Anglicans? All well represented in the UK.Actually, I would expect any sane person to put religion ahead of citizenship. Not to exclude the irreligious from sanity, I say that (given nobody has control over who their parents are or their country of birth) it would make even more sense for a sane person to treat every person of the world with equal rights and respect. In other words, citizenship and religion would be bottom priorities.
The question then is, what relevance is the 80% figure for Muslims?