I wouldn't describe it as "amazing" hiring. I'd describe it as assembly line hiring. The results are amazing: Google/Microsoft/Apple are 3 out of the 4 largest companies in the world by market cap. And there's a hiring process — though I doubt the process has remained exactly the same from company founding to present. The question is how much if any the specific hiring process contributes to the results.

I'd say there's a big difference between a company finding engineers and engineers throwing themselves at a company. The latter is what often occurs with BigCos. They have a big pool of candidates throwing themselves at the company, and the company gets to pick whomever they like from the pool. How much credit to due to the company for picking? Whereas I think you'd give a company more credit for going out and specifically recruiting/poaching one person they want, even if that person wasn't applying for a job with them.