Ads can be useful for marketing moves, e.g. if you sell at discount or just a new product. Otherwise people would never know you have X too (or cheaper) because they remember that you didn’t last time.
But every time I turn adblock off accidentally or on purpose, it’s the same generic shit unrelated to my obvious interests. Nasal sprays, supplements, car dealerships, be-a-programmer courses. I have a non-zero, negative interest in these.
Need? Sure. But there are plenty of things that would make my life better that I learned about through ads.
I do run an ad blocker, because the web has spent too long spreading viruses and malware through ads to be safe _not_ running one. But I don't mind ads conceptually; they just need to be safe, not obnoxious, and not take up more of my time than the placement is worth (ie, a 20s ad pre-roll on a 15 second video).
