A lot of experts got there by being obsessed with one boring-looking thing for an unreasonable amount of time.

Expertise looks like talent from outside because the years are invisible. What usually happened is that somebody found one narrow thing quietly fascinating and kept at it long past the point where a sensible person would have moved on. The subject tends to look dull from a distance, which is part of why the field was open. Time spent is the ingredient nobody can skip.

Notice what you already lose track of time on, however odd it looks to other people. Give it one proper hour a week rather than waiting to see whether it turns useful. Depth in anything teaches you how depth feels, and that part transfers.