Since when have we considered ads something helpful?

Their purpose isn’t to be helpful. They're there to sell you something, and nothing more. Any semblance of helpfulness is misinterpretation and merely coincidental.

Pithy, dismissive, reductionist, and wrong.

Yes, most of the bottom-feeding ads you see these days are along the lines of your description. But those are not the only ads, not the only method of advertising.

Good advertising is informative. iPod ads let people know that iPods exist. An ad for a new album lets you know that a band you like, but don't follow closely, has something you might want to try. An ad letting you know that "Chainsaw Y is on sale this week" is helpful for people thinking about buying a chainsaw. An ad demonstrating "Chainsaw A is as good as Chainsaw B, but costs less" is helpful for people considering an alternative.

The problem is the race-to-the-bottom mentality that has consumed the advertising industry since 2008. This is largely fueled by the ad tech industry which prioritizes things like "engagement" that can be presented in a pretty chart to middle managers, but don't actually mean anything. That's how you end up with all the obnoxious pop-ups and videos.

Ads for chainsaws on a chainsaw enthusiast web site is fine. Ads for a refrigerator I already bought two weeks ago is just a waste in a dozen ways.

> Ads for chainsaws on a chainsaw

Or what Google is doing for years: a wall of ads for "Black & Decker" chainsaws when you specifically search "Husqvarna" or "Stihl", sending the results you want to the sixth or seventh place in the page.