We've observed in the past that there can be an impact when there's a full-page banner present on pages where a user is directly referred from Google, and, in the past, we've advised against having these full takeover banners directly on these pages (via filtering traffic coming directly from Google on the Journeys setup or having a higher priority small banner targeted specifically for Search traffic). We've got details on handling targeting for this here.
There may be plans in the future to start using web vitals on all pages to adjust SEO scoring. The data for this would be collected from users who have opted into data sharing for optimization that use the Chrome mobile browser. The primary score we see impacted by Journeys is CLS, or Cumulative Layout Shift.
Here are some tips on reducing the CLS score here that may be helpful if you're looking to minimize any potential impact from this. As of yet we haven't seen or heard of actual significant impact to SEO based on these scores, but it definitely doesn't hurt to optimize somewhat just in case, especially if it doesn't affect the UX of your current banners much.
Additionally, please see our blog post on How to Get the Most Out of Journeys.
Updated 12 months ago