Google's John Mueller confirmed Google had a crawling issue - specifically saying "crawling for the caches had slowed down for some sites." Google said it was fixed "a while" ago and added that "it wasn't widespread, and that there were no negative effects overall." It was specific to an issue with crawling the AMP cache.
Just to remind you there were reports of Googlebot has dramatically reduced website crawling worldwide but based on what I saw, it seemed like it was limited and not widespread. So I asked Google for more details and Google finally got back to me last night with that statement.
I asked John Mueller and Google PR reps to confirm and John posted this statement last night:
Yes, we saw that crawling for the caches had slowed down for some sites. This bug has since been resolved, and an internal analysis showed it wasn't widespread, and that there were no negative effects overall.
— 🧀 John 🧀 (@JohnMu) November 23, 2021
John also added on Twitter "this has been resolved for a while now, just finally remembered that Barry had asked :). I'm guessing all crawl-graphs will be back at normal in the meantime."
I did ask him to clarify if it was the AMP cache and he said yes:
This was specific to crawling for the AMP cache.
— 🧀 John 🧀 (@JohnMu) November 24, 2021
The issue impacted some crawling on some sites between November 11th and November 17th, as Olivier Papon from Seolyzer noted and as we covered in our previous report.
Google again said this was there "internal analysis showed it wasn't widespread, and that there were no negative effects overall." But I assume if you were impacted, it did have some sort of negative effect on you. But Google has a big index, so overall, compared to the size of Google's index, I am sure it was minor.
Google has had crawling and indexing issues in the past but those issues seemed to have been resolved.
Forum discussion at Twitter.