This is the same Silicon Valley where having Mahbod Moghadam is an asset.
Revenue, especially in the form of VC, is so disconnected from productivity that massive inefficiencies can exist (provided you have the capital to power through them). You can build a sufficiently-successful company ignoring half your resumes. In some places it's way more than half, and there are biases to top-tier schools, biases to personal referrals, etc., and things work.
Also the nasty thing about those sorts of biases is that they're self-perpetuating. If someone else previously hired you for a job you were well-suited for, you now have nice experience on your resume, a good referral, and usually connections. So a company hiring experienced local developers, or a VC firm judging founders by what they've built in the past, gets the result of everyone else's biases.
There's also explicitly some allowance for mistakes if you look like you should have been and could still be successful, ranging from the acceptance of pivots to giving people funding even if their last exit wasn't so great. While useful, this also tends to defang the savagery of the free market significantly.
This is not to say that anyone is guaranteed free money. There's certainly hard work required, and also certainly some blind luck. But the market won't shake out mistakes as quickly as you'd hope.