>Google has very good UX designers, UX researchers, product managers, and engineers.
Google has great engineers/employees that their hiring process has naturally selected for a particular types of people. This doesn't necessarily mean good.
From what I've seen, Google engineers are amazing at solving hard system/foundational problems but absolutely terrible at making good products.
If you were to create a JIRA ticket asking to solve the traveling salesman problem or the like, you'll probably get a decent implementation by the end of the month before you can get a good well rounded product from Google.
Almost all Google products have regressed substantially since inception in just a few years. Gmail was snappy, quick and and had possibly the best UX in any mail client. Now it takes >20 secs on a broadband connection to give me a white-washed mess of a page with no real discerning advantage over the plain html version.
Google has the same problems and challenges you mentioned as any high scale, widely used large corp like Microsoft, Facebook, etc. has. The only difference is that the others go through periods of good-bad UX due to fast pivots, experimentation and luck.
What's the point of having these immensely talented employees if the culture/system can't actually leverage them to design something good?
The reality is that Google was a ground breaking company that rocketed to the moon, made a ton of money due to ads and now hoping to get lucky again by throwing things at a wall to see what sticks.
Google culture is now a highly risk-averse decision process system. It's the new IBM.