> I've tried the deep dive thing a few times and always come out frustrated.

> Generally as a [hobbyist] ...

It sounds as though you expect that reading or doing something once will confer expert status. Instead, try to think of it more like a lifestyle.

If you study something every day for ten years — constantly trying out new ideas to test the limits of the field and your understanding, and teaching others how to get started to develop a deeper intuition and understanding of the basics — you will most definitely be an expert at the end of those ten years.

At no point will you necessarily _feel_ like an expert; that's just a label people give to those who live/breathe/dream a topic deeply for many years.