The problem with spam email is that it operates with a push model - i.e., spam email is forced upon you and you have to do work to avoid it.

In contrast, if you want to avoid Taboola/Outbrain, all you need to do is stop asking content sites that use them to send you data (i.e., don't browse Taboola/Outbrain sites).

Well I definitely don't go to those sites directly. It's usually via links from sites like Hacker News. Adblock blocks Taboola, but I don't use Adblock. I'm not asking you to solve a personal problem for me. I'm saying Taboola is shit. It offers very little value, and there are just enough of us around to click on things of little value to keep reducing the quality of crap on the internet. There's nothing to be done about than to bitch.