Coloured was definitely in use when I was growing up. I reckon the fact it just lumps all 'non-whites' together into one homogeneous group is what makes it offensive.
Aye, I can see that actually.
However, BC was talking specifically about the lack of diversity in UK films, i.e. everybody is white. So he is talking about the lack of non-white people - difficult (for me and my wee brain!) to see what other term he could/should have used.
I certainly don't think it would have went down well if had said "the lack of non-white actors"! And rightly so.
He should have phrased his sentence better, but I don't think he was being racist?