Someone just needed an article and Google likes things they don’t really care about.
Why does it need one?
Haven’t there been other phones with a temperature sensor? I remember some app that crowd sourced temperature data and I could see that being maybe a useful feature. From the article though it appears to be inaccurate so maybe not so much in this case, though maybe Google didn’t calibrate it on the software side because their primary use case hasn’t been approved.
Edit: looks like they can do it through a temperature sensor on the battery, though this isn’t what I remembered. https://news.agu.org/press-release/crowdsourcing-weather-using-smartphone-batteries/