Yes, you're correct. Let's suppose a new viewer visited your channel. What he can see is three things. 1. Banner 2. Display picture 3. Videos. Out of these 3 things banner is the only thing where you can get creative. If your first impression makes a connection you get another sub. Make sure to catch attention in every way. When you're starting new it's not important. No one knows you.

It's important to understand that viewers often make snap judgments based on visuals. A visually appealing banner can catch a viewer's attention and make them more likely to explore your channel further. On the other hand, a poorly designed banner can turn a viewer off and cause them to leave your channel without giving your content a chance.