That doesn't seem like all that different of a problem. I'm certainly not an expert on BBR, but from reading the description, the design goals seem to explicitl

That doesn't seem like all that different of a problem. I'm certainly not an expert on BBR, but from reading the description, the design goals seem to explicitly include dealing with buffers better (by making efforts to not fill them to the max) and being less skittish about packet loss. Specifically, the description (in the git commit) says it has a "congestion control algorithm that reacts to actual congestion, not packet loss or transient queue delay" and that it estimates the size of the queue it probably created and paces packets in order to "utilize the pipe without creating excess queue". (And that last part addresses large buffers. Even if they can't be turned off, they only fill up if you send enough data to fill them.) Obviously it isn't magic and there is only so much any algorithm can do in the face of a cruddy physical network layer, but the traditional algorithm makes a bad situation much worse than it has to be, so there is still the potential for a newer algorithm (like BBR) to make a big improvement. Anyway, more to the point, cruddy wifi is what a lot of people use to browse the web, so it's not surprising to me if Google tried to account for that in their design.