Mark Ronson was still in his first few big years when DW did that, so perhaps he didn’t want to muddy waters. He’s certainly in the position to speak now though.
The irony is, if it weren’t DW, DW himself would want to shut down the masses of chat everyone’s having right now. You know, big twitter post kind of tit.
the fucker hasn’t said a thing, obviously.
Mark Ronson is a victim and not obligated to do anything.
He already spoke out about it many years ago, diffusing the situation (as did Walliams, who apologised and said he would stop that stunt). This was necessary at the time for PR reasons; if he'd been openly upset, he would have been treated as someone whiny and pitiful who can't take a joke.
If Ronson now spoke out, it would contradict his earlier statements, and he would get raked over hot coals if it went to court.
This is what he answered in an interview:
Has there been a more awkward moment in your life than when David Walliams ripped your pants off on stage last year?
No, definitely not! I’m such a fan of Little Britain [Walliams’ comedy show] that it was so ignorant of me to think that nothing bad was going to happen if I was on stage with that man. I’ve seen them a lot since and we get on absolutely fine – it was just a bad night.
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So he's already self victim-blamed and downplayed it, which is a sad a reflection of noughties attitudes and what he had to do.
To be honest, this was the right thing for his career, to avoid being known as a victim instead of a talented music producer.