The key criteria is this report are;
Core Web Vitals – This is a test of speed and stability of page loading experience.
Mobile Usability – Examples of errors: text too small, clickable elements too close together, content wider than screen.
Security Issues – Your site will be disqualified for all URL’s with any security issues.
HTTPS usage – A page must be served over HTTPS for a Good grade for page experience.
Ad Experience – Typically, advertisers use a Landing Page (independent of the main website) to engage a specific call to action from users. What is important about this Page Experience grading system, is the evaluation of all pages on a site, not just a single one. If your landing page has been performing well, but the entire site has issues…your ads ranking will be affected.