I think we have to be careful about defining "in tech." If it means founding employees of technology startups, that's very different from working in technical fields. The latter is approaching gender parity albeit slowly.
Yes, I'm talking about companies "in tech." You defined "in tech" as employees of technical startups, and I'm saying that even larger technical companies have these same issues, so restraining "in tech" to mean startups is not a necessary distinction. Sorry I was not clear on that.
No, I merely think software houses reflect the gender makeup of the industry fairly accurately. Hell, I would be surprised if it turned out that that anywhere near half of software workers in general are women; this would imply that the majority of female software engineers work independently. I find that extremely unlikely, given how few women enroll in computer engineering degrees at universities. My point is that Microsoft, a mature and established software company, has a hard time finding female engineers, and this reflects the state of the industry as a whole.