From the article:
> Gmail product manager Paul Lambert said a company research scientist discovered the problem in January when he typed “I am meeting an investor next week,” and Smart Compose suggested a possible follow-up question: “Do you want to meet him?” instead of “her.”
So really, this is a fairly reasonable decision whereby it doesn't infer gender from signals such as profession.
The article doesn't address this, but I wonder what it would do given an explicit gender, e.g. "She's the investor I am meeting next week."