That doesn't mean ads are necessary though, frankly any system which depends on spending more than your competitors will never produce the best recommendations. Instead I learned to first build a list of companies in a space, then research those companies. I use things like Wirecutter, Reddit, and Productchart to help decide as well.
What I need aren't ads; I need good, user-centric, recommendation and discovery products. Sadly we fell into the local-minimum of ads instead. That said sometimes I do choose to let a company advertise to me in a specific channel (separate email or social media account) so I can keep up with their products and potential deals. That seems like a good middle ground for me.