I don't think it's just the GG stuff though. It came on the back of an endless stream of shit from plenty of other people, and it's somewhat not surprising that a 'personality' like GG saying something similar would be the thing that broke the camel's back.
I'd also say that while it's perfectly true to say that in and of itself, as you say, being woken up by sex does not necessarily constitute rape, many are using that as a way to completely disregard the idea that it ever could. And that's the problem. Just because, as I said, one couple in one set of circumstances might see it as part of their consensual sexual relationship, it's perfectly possible for the same act to have a completely different meaning in another context with another couple. So this isn't about saying "being woken up by sex = rape," this is about saying that it can be - as can any other kind of sexual behaviour, awake or not - and much of the anger seems to stem from people outright coming out and saying "nope, not rape, I should know, my girlfriend wakes me up with blowjobs regularly."