FTEs is one way to slice it, but kind of dumb.
Seattle is home to two of the five biggest tech companies in the US.
Boston has had an IPO every year for the last ten years that exceeds any in NYC history.
LA has had the only 11-digit IPO in the last five years, outside of the bay area. It's also capturing the zeitgeist in a way that NYC no longer does (that's subjective, of course, but I'd debate it).
Just by market cap, Sydney's three biggest tech co's would are more impressive than NYC's.
NYC is an awesome startup city, but the idea that it's the clear #2 is silly.