also one should always be skeptical about the extent they believe they are not influenced by ads. that runs pretty deep. you say you instinctively don't trust it. but when the time comes to buy something, you won't automatically steer yourself towards a product that you have never heard before just because you have not seen an ad for it. having some names in your mind, even them showing up when you do research creates influence.
Marketing, whether they are external firms or internal teams, have their own incentives, just like anyone else.
But… Personally I like good marketing and I‘m drawn to services and products who do so.
For example tech and games sometimes do very good marketing by providing educational resources, transparency through blogs/vlogs etc.
Some products are focused on a high quality, sustainable niche, and they do very pronounced, sometimes humorous over the top ads.
I „mistrust“ marketing if it wants to sell cheap crap in a disingenuous way. But I‘m glad to see ads for interesting, quality products.