I agree with your statement, but I'd say that at least Google has been advancing their machine learning/AI front under Sundar. But that's about it. You can clearly pinpoint the moment Google started going downhill the moment he took over, whether this has been the result of his leadership or due to the Alphabet restructuring, I don't know.

I won't make any comment about going downhill or not, but the Alphabet restructuring you're talking about came after Patrick Pichette left and Ruth Porat took over as CFO but before Sundar became CEO.

If there was a clear boundary between old and new Google I'd say it is around the time that Patrick and Alan Eustace left. Other changes in senior leadership happened in that same couple of years.