In June 2021, Google will start using Core Web Vitals as a ranking factor – therefore, these metrics could affect your SEO performance.
Core Web Vitals will be part of the new Page experience signals, together with HTTPS-security, safe-browsing, mobile-friendliness, and intrusive interstitial guidelines.
Core Web Vitals will affect both mobile and desktop organic results, as well as whether or not your site appears in Top Stories. Previously, your site needed to use AMP to appear in Top Stories. That will no longer be the case when Google rolls out the change, but your site will need to meet specific minimum Core Web Vitals scores to appear in Top Stories.
In short: if you care about your SEO performance, improving your Core Web Vital scores is now mandatory.