I have the same problem and my diagnosis is that is a symptom of not having a deep bond with any of those interests. I've deceived myself that the ease of discovery will automatically transfer to mastery.

I realized in a world of abundant and instant knowledge, I've been applying the laws of scarcity: "I won't be able to do Y and Z if I spend too much on X". Hence the anxiety to get to the Y when doing X. But it's not going to be a finite list ending in Z. It is an infinite stream and that I have to treat it as drinking from a river vs a cup.

Lately, I've been deliberately giving up on reading about topics, unfollowing people at the edge of my interests and focusing on the areas that are more central. If you look a little bit, you can identify a couple of interests that are stronger than the other. Then it is a matter of eliminating the time spent at the edges.