(Sorry, couldn't help myself! Many people still refer to it as a FAANG company)
Netflix doesn't come close to matching Microsoft or the others.
Engineering chops? Well-run organizations? Doing interesting and fun work? Absolutely. Probably even more so.
It was coined in the Ballmer days, when MSFT's stock price had been stagnant for about a decade, so no surprise that it got left out. Things are different today though.
Even there the content produced by their competitors is getting bought by Netflix later down the line for international distribution.
However GAFA probably sounds better to the ear when pronounced the French way than the English way. This may explains that.
SUP FAM.