Even though I wouldn't voluntarily opt in for ads on my Facebook feed if I had the chance, but some ads are so good that I am sometimes even thankful when I see an interesting promoted product
Idk, when things were different, I actually read ads on paper, because it was interesting what companies can offer, and it was versatile. It was like going to a monstrous store with shelfs full of different goods and descriptions. You’re asking how to target a specific interest? A directory. I’d go to a tech section (and many more) weekly just to keep up with the world. I’d share good findings with my friends and relatives, buy interesting things which I know much better than FB ever would. Today directories are dead and I have NO, completely NO way to do that, except by the chance of seeing something on HN or few other sites. Github awesome-something lists are a proof for that: you just can’t reach good stuff with how it all works now.