Your longform is hurt because the audience you have is mostly form short content (that I can see) YouTube treats those viewers separately often, so they often donβt click (or even get shown) your longform, and the weak early audience engagement limit your reach. Your previous content also doesn't have a huge audience overlap with the new content, so existing viewers arenβt super valuable for you. Itβs fixable, but it usually means putting a lot more effort and taking a lot more time/making many more videos to build an audience that will watch.
Every piece of content someone watches builds a link to your channel for that viewer, and even if the content doesn't fully match up with what that viewer watches, YouTube will still show it to them in a lot of cases, but they aren't interested.
If I were you, I'd build a new channel for content that isn't the same as your older content, and grind that instead of posting on your existing channel
@FBI People in the comments assuming that just because thereβs an em dash that itβs AI-generated π
Em dashes were common in formal writing long before AI.