The media portrayal of the tech world would be more impactful if it weren't so hyperbolic, dramatized, and skewed. There are myriad valid complaints about the tech world, but Facebook paying you for you posting your photos is not one of them. Facebook is free. Google search is free. 15gb of gmail/google drive is free. You get those free, truly amazing services for nothing because the companies found ways to generate…
They aren't free. You pay for them in high prices for good and services. Those companies pay advertising which increase prices plus their tech size profits. And because the stock market machine demands greater and greater profits they need larger stronger monopolies to generate those obscene profits.
Your reasoning is extremely fallacious because you're overlooking a lot of nuance.
Yes, it is true that in aggregate part of the advertising costs get passed on to consumers. How much exactly depends on macroeconomic factors, industry dynamics, pricing power of distributors and retailers, and hundreds other variables. But you are right that in aggregate a non-zero amount of the advertising costs get passed on to consumers.
However, advertising is valuable to advertisers because it works to some degree. And it works because people are influenced by it. Now, as an individual I have no control over what other people are doing and so I have no control over how valuable advertising is and how much is being spent on it and how much is being passed on to consumers. Therefore as an individual I look around me and prices are what they are and already have in them advertising costs which will not go up by me using service. Therefore as an individual the marginal cost of me using these services is effectively zero (imagine the ratio between the value of advertising to me and the aggregate value of advertising, that's effectively zero). As an individual those services are free.
So it depends on what your definition of "free" is. A) Would prices be lower if advertising didn't exist? Yes [0]. B) Would prices be lower to me if I didn't use these services? No. The thing is that in definition A) I don't really have a choice, so it's irrelevant. I only have a choice as an individual.
[0] And even here some people will disagree with you. What I call "free market fundamentalists" will argue that No, they wouldn't, because the advertising leads to higher sales and greater operational efficiency, so that advertising costs are exactly offset by lower per-unit costs.