I also have a bunch of 'things' that have been bookmarked for years: mostly movies and articles, some projects. This stockpiling has become tsundoku for more than books [1].
On one hand, divorcing myself from the initial impulse to consume or create something helps filter down to what I am and will be truly interested in. On the obvious other hand, the backlog grows to the point where I get paralyzed by so many options and the perfect ideas in my head that I end up not doing anything.
I struggle with the same, and I have exactly the same thought process.
Occasionally, I have a filtering session when I am going through everything and narrowing them down, however extra items are appearing until the next filtering session and the same goes again. It is a vicious cycle.
Did you save off your links for the tutorials you watched etc? I've messed with SP in the past but never got comfortable with it so additional tutorials would be rad.
I had sonic-pi bookmarked/planned for more than 5 years. It is sad how most bookmarked items never get viewed or they are postponed to eternity.