You’re right that they don’t need to, but in reality they do whether they announce it or not.

In 2017 I tested this at home alone in my apartment in by myself using my smarphone by finding a site with lots of banner ads, monologing next to my phone about a topic with no relation to my current life at the time for about a minute, then refreshing the page. To my horror, the exact thing I was monologing about showed up on every single banner ad. Nothing in my life was going on related to that topic and the only thing connecting me and the topic was my own vocal words.

That was the moment I decided to avoid Google/big tech for the rest of my life.

In 2021, I bought 4 4TB bad HDDs for $65 each. I decoded to buy a spare a couple weeks ago in case this shit decides not to stop and an hdd fails since most of my shit is on my NAS. It was $170 for the exact same model.