It is way too early to say whether or not Google is failing in AI. The only thing that is certain is that lately things are not going smoothly for Google in AI.
Although usually I found David's posts pretty interesting and well written, this post does not make a lot of sense.
"Later, that the vaccine would prevent you from getting the virus. Finally, that if you were vaccinated, you couldn't spread the virus. All of that, and plenty more, turned out to be false."
It's full of questionable claims (see above) and his reasoning is hard to follow, unless for anti-vaxxers maybe.