Trevor Sinclair can feel however he wants about the Queen; it's his opinion and it's his life experiences he's basing it on.
If I were him, I probably wouldn't have spoken for all 'black and brown' people and I also, as a public figure with a job at a popular radio station, probably wouldn't have expressed my viewpoint as publicly as he has, as he'll likely now be obliged to apologise and will likely be sacked.
That said, he's entitled to feel that way and it's not for any of us to tell him he's wrong.