I generally get downvoted hard when I raise my hand as an advertiser, but here goes.
I think scapegoating advertising is a mistake, because I think we're missing the real problem.
Yes, advertising can and often is unethical and harmful. I can't speak for other advertisers, but I take ethics very seriously. I don't participate in advertising aimed at making problems seem bigger than they are for the sake of selling a product. It's effective (in terms of sales), but I wouldn't be able to live with myself if I did that.
But: What exactly changed about advertising around 2010 if we're going to say advertising is responsible for a radical decrease in mental health since that time?
On balance, I don't think advertisers today are less ethical than they ever were. The same bad actors exist. There are more laws today to prevent the worst abuses, but there are still ways to legally manipulate the public that I would consider horribly unethical.
Yes, we have access to more data. But from my perspective, I haven't seen data used effectively for much more than targeting, i.e. prioritizing ad budgets towards the people most likely interested in your product. It still makes me uncomfortable, but can that alone impact mental health at these levels? I don't think so.
And so my problem with scapegoating advertising isn't that it's unfair to advertisers. We deserve a lot of the vitriol sent our way. My problem with it is that if we're wrong in our diagnosis, the real problem(s) remain unchecked.
The vast majority of the people I know in advertising didn't want all this data in the first place. We were happy to just work on creative ideas, to try and paint a product in a new light so that the general public would take notice.
What changed is social media, and the social media companies themselves. I truly believe the problem is with engagement metrics and all the crap they do to keep people addicted. Advertisers, in turn, are forced to play the game, because it's the only game in town. If you're not advertising on social media, you might as well not exist. And if you don't play the engagement game, you might as well not be on there at all. It's a trap.
That's not to say there's no one in advertising who is genuinely content to do harm. They exist. They've always existed. But they didn't, and couldn't have, created the platforms and the algorithms that multiplied the problem since 2010.
Further, when I look at my own use on social media, the most toxic content isn't sponsored content or ads, it's stuff that's gone viral by content creators and political actors. It's "recommended content" that should have been flagged as wildly inappropriate rather than promoted for more engagement. Saying the problem is advertising misses all of that horrible stuff.
So again, not trying to say advertising is good for the soul. Not saying it's a net positive for society (although I think whether or not it's a positive has more to do with WHAT is being advertised than the act of advertising in it of itself).
But let's not mistake advertising as the cause of the mental health crisis, at least not without solid evidence to back that up. I don't think the evidence in the original post would support that conclusion at all.