“On-page SEO (also known as “on-site SEO”) is the practice of optimizing web page content for search engines and users. Common on-page SEO practices include optimizing title tags, content, internal links and URLs.

This is different from off-page SEO, which is optimizing for signals that happen off of your website (for example, backlinks).

Does traditional on-page SEO still make a difference in 2020?

Yup!

Even though Google is MUCH smarter than it was back in the day, they still use old school stuff (like looking for a specific keyword on your page).