So, are you saying that if I follow the instructions in the video, then change back from a static page to the dynamic page, the banner issue will be fixed?

Because from what I can see in that video, all that the static page setup did, was move the “grey block” problem from the home page to the blog page. As can be (briefly) seen at the 3:45 mark in the video. The person who made the video quickly scrolled down, maybe to get the grey block out of sight as quickly as possible, but it’s there.