I’m sorry you only worked with terrible, unethical, incompetent marketing people. There are good ones, just like there are bad programmers who do all sorts of terrible and dumb things without creating universal truths about programmers.
Of course marketing people do a valuable job in terms of figuring out how to sell things and minimize the gap between producers and customers. But - just like engineers - there are lots of cynical and amoral people who work in that industry who make things worse for everyone else. By contrast, I can't think of any society that is suffering because they don't have enough advertising.
If anything, societies suffer when good marketing is absent—because that’s when bad actors fill the void with misinformation, hype, and scammy tactics.
If that's your metric, I can confirm the GP's statement, at least when it comes to online marketing people. Increasingly, I can not find the right products and services online.
Except, marketing too is a market for lemons. Scammy marketing outcompetes good marketing. Simple as that.
Deceptive brands burn their audiences, lose customer trust, and either get regulated out of existence or collapse under their own churn rates. Meanwhile, companies that invest in clear, honest positioning, strong customer relationships, and long-term brand value consistently outperform in the long run. Apple, Patagonia, and Tesla aren’t winning because they spam pop-ups.
If marketing were purely a race to the bottom, all successful brands would look like clickbait farms. They don’t.