They could have just asked.

In fact I can answer this for you, since I was the relevant director (IE Go directly reported to me)

It was driven by the core team, and more particularly, the leads and what they want to be trying to do.

I have provided precisely 0% of the vision there.

Further, the org/etc they belong to has changed (a very small number of times) over the past 10+ years depending on the Go team goals, not depending on Google's goals.

(IE when their goals have changed, or the org goals changed, Google has put them in a place that aligns with their goals, not tried to align them to the goals of the org they belong to)