That's (a) a different argument than the competition is "too risk averse", (b) subjective, and (c) arguably the result of a number of flywheel effects. That is, Bing's ability to compete is hampered by the fact that Google already has an overwhelming majority of search traffic from which to learn and improve.
For example, from the second filing I linked to:
> After search began appearing on phones, Google started logging information about user location, swipes, and other user-related movements. PFOF ¶¶ 1003–1004. This data is now vital to every aspect of search, including figuring out where and when to crawl specific websites, how to index the information retrieved from that crawl, what documents to retrieve from the index in response to a user query, and how to rank the retrieved items. Some elements of Google’s search engine are trained on 13 months of data—a volume that would take Bing over 17 years to accumulate.
