CBB5 came right off the back of one of, if not the most popular civillian BB series with the British public. It pretty much ruined all the positive publicity that BB7 had generated the franchise. In my opinion I think that, had CBB5 not happened, BB would probaby still be on Channel 4 now getting decent viewing figures still (higher than C5's).
But then again there would also be drawbacks, e.g. a woman of colour never winning a UK BB series, the bullies never being exposed for their real selves etc. It would've meant Emily wouldn't have been ejected in BB8 but then again, the cast might have been completely different.
It really gets you thinking tbh doesn't it