the 2011 census shows the uk population included 6.92% was of asian origin. for whatever reasons, these are practically invisible in football. the census showed 87.2% were of white origin, with around 5% black or mixed race. as percentages excluding the asian groups, it scales up to around 94.5% white and 5.5% black or mixed race. 4% is below this 5.5% and below the other 5%, but it isn't so far below that "poor" is an apt description. you have to cite some sort of context, and there's not been much of that on this thread.
https://en.wikipedia.org/wiki/Demography_of_the_United_Kingdom#Ethnicity
the number of foreign managers in the premier league exceeds the number of british managers. there were 33 managers in the pl this season, 17 of them foreign. of the 16 british managers, four of them managed west brom.
https://www.premierleague.com/managers
That sounds a bit like straw clutching to me. The key stat is that BAME - mostly black - players make up about 25% of players in English football and just over 4% of coaching positions. That fact is all the context you need. And, with reference to your second paragraph, no one is saying that they should be given the top manager's jobs (and managerial jobs only take up a small number of these coaching positions - and the British quota gets a lot higher when you take in youth coaches and the like). No one is saying that managerial appointments shouldn't be given on merit, as is mostly the case in the Premier League. Is attempting to correct this problem by simply adding one more BAME name to a shortlist really that big a problem?