I can tell you from experience that impressive hero banners and animations that get the user's attention reduce bounce rate. That might not matter if you're established and you get customers via product market fit and word of mouth, but for small shops trying to land early customers it's crucial.

It makes a significant difference if you’re talking about a web page that’s more like a product brochure, or if you are talking about an application the user wants to get a task done with. The latter shouldn’t have “impressive hero banners”, and “animations that get the user's attention” only when the user needs to be made aware of an important application event.

The assumptions buried here are that bounce rate is accurately measurable and that reduced bounce rate correlates to increased sales.