After the demonstrations that money not in-hand is likely to evaporate before you can get it, is that still the case? Personally I ignore equity completely when deciding if a position is well paid or not. Equity is like a lottery ticket a friend buys me: I'll keep it around and when the time comes I'll see if I won, but I'm sure it's actually worthless.
I suspect that just means you don't want to help someone start a business where it is hard to measure how effort in generates money out. If a buddy shows you a picture of pirates burying treasure in your backyard and then hands you a shovel, it isn't a big stretch to imagine you digging a hole for a few hours for no pay :). On the other hand, an idea scribbled onto a napkin by a non-expert isn't so compelling without cash to go with it.
Your comment hints at the issue. It isn't measuring effort in vs money out, it's likelihood of reward for effort. At this stage it's clear that if you count options and even equity as zero you'll often be right.
If a startup hands me a picture of treasure in some place I can quickly get to (i.e. little investment on my part) and a shovel, I'll invest a couple of hours for the chance of getting rich. If they hand me a lottery ticket that they can void if it did happen to win, I'm not going to spend months or years slaving away for that.
