Pre-2008 not all banks were hugely profitable. Some investment banks were and some smaller companies. The tech sector isn't that dissimilar. Salaries in SV show that not only Google and Facebook are willing to pay $200k+ for engineers, most of the industry will (and usually can).
As tech can't print money, these salaries must come from somewhere. And at some point those sources won't be able or willing to provide it. Maybe that's a soft landing, maybe harder. I don't know but as I said previously, I'd be surprised if tech's the first industry in centuries that channels wealth into the hands of few (including SV landlords) without any consequences.