Sort of agree, at least I did at the time, but in retrospect and looking at what has happened since, and especially who has pushed for it, endorsed it, and continues to be instrumental in expanding the scope and reach, I don't think that's the full story.

In what way are the goals of identity politics any more clear? Most of the time the only obvious objective is "winning on Twitter".

Occupy didn't have clear goal, but it was dangerous in theory. Letting it simmer could have lead to something more dangerous, a popular movement demanding significant reforms, for example, setting capital gains tax to match income tax. Identity politics in contrast is not dangerous and has no potential to become so.