I disagree in most of that and agree with a little.

I do not think in general that ethereal throwaway content is promoted or does very well at all.

I agree on the fact that it doesn't work the best for people who post once or twice a week. However I would say that is the same for many platforms. You have to build an audience. it is harder to do that if you just pop on and off occasionally. I think that is the same for most types of social media