You might not be able to change an individual's choices by very much, but all these tiny nudges in aggregate push society more and more towards unsustainable levels of consumption, without improving happiness.
Most cars I see around on the roads are family sedans and not trucks. Some are SUVs but those are not for hauling trailers - those are for hauling groceries and kids to the soccer games. So I don't think the trailer one works very well :)
And actually if you take about prestigious, two-person convertible looks much cooler than your standard family-size SUV/minivan. But people that buy the latter usually buy it not because they want to be cool, see above.
I think the problem here is not the ads but that people are gullible. If those people can afford to buy a car which can pull a trailer when they don't need to its not because of advertising, it's because consumption makes them happy.
That's irrelevant to the topic of ads.
Clothing is of cultural and societal importance for individuals in a group and we've become rich enough to afford to essentially buy items of clothing as we please.
This runs quite deep in human society. Look at every human groups on the planet even the most isolated and 'primitive'. People wear symbols and try to make themselves more attractive.
Clothing ads are just a 'symptom'. Our behaviour runs much deeper than that.
My problem is not that I want to see ads that are more "relevant", it's that I don't want to see ads. I don't care what you're selling. If my problem that you're trying to solve is really that important, I'd be actively searching for a solution, not waiting to be enlightened by a targeted advert.
Adtech evangelists seem to think that my biggest problem is a burning surplus of cash that I'm just desperate to get rid of. If only I could find more products to buy so I could be liberated from the pain of having money in the bank! Er, no thanks. I'll put my spare cash towards saving for a house and retirement and the occasional luxury; save your bullshit for the people who don't know how to install Adblock.
(The other way I use my spare cash on is to pay directly for content, because almost everything that's wrong with the Internet and modern media is the fault of the current ad-driven paradigm, and only future I want to live in is one where ads are dead.)
The whole point of advertising is getting conversions: convincing people who previously weren't going to buy your product that they should buy your product.
Some of the people that are converted just didn't know about your product, some had forgotten about it, some thought a competitors product was better, etc. So there is a sense in which the vast majority of people you convert aren't people who specifically "don't want" your product. And you're definitely right that this isn't Inception-tier infiltration of the mind. But at the same time, the conversions you are trying to get are the people who don't want your product yet, but just need a tiny push to want it.
But it's quite likely that the majority, or at least plurality, of ad spending goes to the changing minds kind of campaign. This is especially visible in the massive popularity of lifestyle marketing campaigns, that seek to create a particular image making a product (or even type of product) more desirable. Think of the Coca Cola Christmas, "green" cars, hyper-technologized "smart" fridges/washing machines, fashion brands, Apple's success a few years ago in convincing people to change their phone each year etc.
You also shouldn't forget the disgusting world of children's advertising, where often the goal is to convince children to nag their parents or friends about an item - often by explicitly showing this type of behavior, which works wonders with small children especially.
Yes and no.
The problem with digital advertising is that the only part that's easy to measure is what's happening at the bottom of the funnel. Which means that a disproportionate amount of effort and attention gets spent on those campaigns.
There's a whole layer of awareness advertising which, while it's not about influencing behaviour, is certainly about building consumer awareness of a brand or product to later build purchase intent.