In-depth analysis of QUIC, but to me the most important take-aways were this:

1. "QUIC now represents a substantial fraction (estimatedat 7%) of all Internet traffic"

2. "We found that when competing with TCP flows, QUIC is unfair to TCP by consuming more than twice its fair share of the bottleneck bandwidth."

The paper is 2 years old, so the amount of traffic has probably increased. Unless they've fixed fairness wrt TCP, Google is invisibly grabbing more bandwidth than their fair share.