Google's John Mueller said that an issue with Cumulative Layout Shift scores would not be a reason why your website suddenly and significantly drops in the Google search results rankings.
A Reddit user posted asking "Sudden decrease in organic search traffic - is Cumulative Layout Shift to blame?" John Mueller from Google posted his classic one word answer - "No."
The question went on to ask, "I noticed a few weeks ago a huge drop in my organic search traffic (consistently -50% YOY). I'm trying to diagnose the cause and the only thing I can from from Google Search Console is 3,000+ mobile pages being identified as having "CLS issue: more than 0.25 (mobile)." I believe the culprit is a slow-loading Google ad banner that pushes everything down. I had added it to my site about a week before the traffic decrease. I've removed the ad unit and am waiting for Google to validate the fix. Would this be a potential cause of the sharp decrease?"
John Mueller said, "no."
That is it. Here is the screenshot:
This should not be new news to any of you if you read this site often. Google has often said that the page experience signals, such as core web vitals and those signals within it are not significant ranking signals and do not make a big difference in your overall site's ranking within Google Search. Previously, Google said this is a ranking factor, more than a tie-breakerpage experience update is a tie breaker in the past. Gary Illyes from Google said the page experience update won't be drastic and might be more like a tie breaker signal than something really big. John Mueller of Google said this won't be a drastic update like other Google updates, he added it will be a slow rollout and not felt too much. Danny Sullivan of Google said it won't result in a massive change when rolled out. This also includes INP and that CWV should not be a top priority for most small businesses.
Forum discussion at Reddit.
Update: The next day at a Google SEO conference, John said don't over focus on Core Web Vitals:
Coming on 2024:
— Aleyda Solis 🕊️ (@aleyda) October 24, 2023
* INP (Interaction to Next Paint) in CWV
* but also, don’t over focus on CWV #SCLzurich pic.twitter.com/mJ4jYp3zPD