What's missing from this guy's evaluation: whether or not any of these unicorns are close to or at profitability, and what their actual market potential is.

If the businesses are based on bullshit, then he's probably right. If the valuations truly are wildly out of control (and it does seem like it), then sure, they're due for a correction.

It's also worth keeping mind that if there are 144 of these startups, 90% of them is 129. That doesn't add up to that much money in SV terms. This seems like a tempest in a teapot. People love to make headlines, it seems, with "OMG bubble OMG!"