As a counterpoint, the prestige of the big 4 can be helpful going from a software engineer to a technical co-founder role. Investors like seeing external validation with that kind of weight.
It's kind of funny that a position at one of those companies is now the new mark of prestige instead of a college degree or something. Shows how far the university has fallen.
Does it? Unless things have changed, graduates of elite universities are disproportionately represented at the AppAmaGooBookSoft companies. It seems more accurate to say that those companies play a similar role to HBS and Yale Law.
Is it Valve?
Even back before Google existed, having MS on your resume would open doors at software companies.
Google has always been a gold star.
But it isn't instead of universities, it is as well as. Stanford/MIT/etc will have the same effect.
Maybe it shows how little I know, but I think Valve and other companies who do this are doing themselves a disservice by basically using Google's recruiting department as a passthrough (and, as an autodidact programmer, I feel essentially the same about people who put it all on educational pedigree -- this isn't an endorsement of the baseline credential, just an acknowledgement that what constitutes it is shifting). It feels like an admission that they don't know how to hire, so they're effectively offloading that responsibility onto companies whom they believe have thorough vetting processes.
Also the Big 4 are changing every few years. Is Twitter still considered part of that group?
It's clearly currently five. In order of market cap: Apple, Alphabet, Microsoft, Facebook, Amazon. Note that these are now the five biggest publicly traded companies in the world, not merely in "tech" (a clearly archaic categorization).
This isn't exactly a strong line though, since all are at least diversified into things outside software.
Nevertheless, that was the original reasoning.