In Western business culture is “silence is consent?”
I think it is. For example, if you don’t tell the VP of Marketing that his campaign is deeply problematic in the meeting, well, aren't you then automatically a supporter of his campaign? Defaults matter in more rules-based Western business manners. No protest at that particular time, no hands raised within that window means you are going with whatever is being proposed and you have little to no rights to conduct a future review.
In Chinese business culture, I don't think silence is consent. I think silence is a degree of acquiescence, but definitely not consent. A lot happens in side meetings and in pre-meetings, so much so that this particular meeting may just be a formality. Silence in that meeting, or any meeting never has the finality that it does in a Western context. It is not as rules-based. Therefore, with future ebbs and flows in the balance of power amongst all stakeholders, the likelihood of a review or a reopening and reconsideration of the past circumstances of the "silence" persists and can't really be eliminated.