In the past, customers have repeatedly asked us whether our personalization actions influence their Google rankings. Our answer: All we can say is that we have closely analyzed the website performance on the SEO side with various customers in the past and were not able to determine any negative effects.
Now it is official – at least as official as Google communicates its ranking factors: In an article by the Search Engine Roundtable on April 10th, 2019, a Twitter request to Google was captured on a screenshot:
Instead of playing out dynamic content on pages via URL redirect, John Mueller (Webmaster Trends Analyst at Google) specifically advocates a dynamic adaptation of content – at least if the primary content is constant.
We are pleased that our previous experience with the personalization of webshops using dynamic content elements has once again been confirmed here.
EN 
DE