Fresh-out-of-college engineers weren't making $300k, let alone $500k. I'm not sure where you got these numbers. Even at the highest paying BigN, fresh grads don't typically get over $200k.
> It was very hard to recruit when all the best and above average talent just got sucked up into the giant companies that build advertising machines in SV.
The talent crunch has been getting worse for the past couple of decades. Don't expect this bear market to be some sort of cataclysmic change that would reverse the trend permanently, not anymore than 2008 was. Even 2001 only lasted for a fairly short while, and demand for top tech talent back then was a tiny fraction of what it is now.
That, essentially, is why this crunch exists: the number of highly talented engineers has remained about the same for decades, while demand skyrocketed.
Also, what other companies stand ready to receive all this "above average" talent? Small companies, which in this market, are having an even tougher time? BigN by and large haven't gone through massive layoffs, while small and medium-sized companies are getting massacred. Like Snap which lost 90% of its value.
Startups are in an even worse spot. Funding is going to be very tough for the next couple of years, and startups have been extremely stingy with their equity. That's why they're having trouble recruiting: BigN are paying far better, while startup are much riskier, and if they do succeed, there's very little upside for engineers who are granted ridiculously small amounts of equity.
I wouldn't hold my breath for all these "above average" talents being desperate enough to accept bad deals from startups that don't want to give out equity, nor is that a desirable outcome of this situation. Startups should either start granting more equity, or start gasp targeting less talented people.