IF I have to pick one thing [from reading your article] that would be:
'I have such posts because I had topics I wanted to talk about'.
The courage to do what your heart is after 👏 I'm not against of attracting tech opportunities from writing but I'm more inclined to do what I love to do.
You're in a flow-state when you do what you love.
Lastly, you also nailed it that narrowing down is the key. In this one can kill two birds with one stone [doing what we love and attracting the opportunities as well]