> Facebook, Apple, Amazon, and Google

We don't all work for these 4 companies.

There's lots of fluctuations in oil/energy, car makers are predicting slow downs (which may have bigger implications in the near future), Brexit effects are still being felt and worked out, and our own Fed doesn't seem confident enough in the near term economy to commit to raising interest rates in the near future.

He does:

> Vulnerability is here. Falling valuations. Layoffs. Shifting geography.

He also isn't saying the winter is coming, but that things might be changing and we should be prepared if they do

> To reiterate, I’m suggesting preparing to make good decisions if the rules change drastically.

That's a counter-indicator for the success of startups. We saw the same thing in the game industry in the late 90s: the consolidation of power into a few mega-players means the small fry all get wiped out or bought for scrap.

I interpreted the ASOIAF reference to mean what it means in the books: it is a question of when, not if, Winter is coming and you'd best have a plan in place for whenever that may be.

Facebook, Apple, Amazon, and Google also have established business models in-place. Many younger companies are burning investment dollars in the hopes of turning profitable or being acquired.

He never does state that, he says "not saying winter is coming". I.e., regardless of what the future has in store, put yourself in a favorable position.