I think the last couple of years have sown & grown the seeds of concern around some of these buzzy "valuations" for businesses that are years into their execution stage, burning more cash then they make, and still appear to have no path towards addressing that scenario.

The preferred business model still appears to be: 1.)Grow large enough that you can buy your competition and establish a monopoly or 2.)Become large enough that your competition acquires you.

I haven't seen many recent successful pivots from those two stages into a sustainable, long term business.