Not even their ancestors at colonial times benefitted much from it: the industrial working class of Britain was in dire position despite Britain being a colonial Empire. That money and power went to the ruling classes and their middle class bootlickers.
I'm not talking about that happened thousands of years ago either. I'm talking about the conditions of the working and poor classes when Britain was a colonial superpower, like througout the 19th century. Hell, even post WWII most of Britain working classes were living very modestly, in wretched wretched council houses, and with low means.