Two main reasons, in my view :

- It's way more profitable for the advertising platforms (that remains to be seen for the advertisers, see point 2) because you multiply/combine the number of different audiences infinitely or so => more campaigns, more budget...

- The user engagement metrics (clicks on your ads, return on invest, etc) are waaaay sexier with targeting advertising. It's pretty logical, since people you adress your content with are much likely to be at least a bit interested.

Privacy and user's anger might effectively have an impact, but we can also suppose advertising platforms will adapt anyway.

This is exactly what DuckDuckGo does and what Google did prior to targeted tracking and advertising. It's basically the old school web advertising model. I'm guessing it's not as popular anymore because it's not as profitable.

By most measures, both for ad platforms and advertisers (and subsequently users), audience-targeted ads outperform context-targeted ads. You could go back to a world of only context-targeted ads, but publishers would need to make their business models work with lower RPMs, advertisers with lower ROAS, and users with less relevant ads (to them).

The ads you see are determined by a combination of factors:

1. The bid price

2. The clickthrough rate of the ad (must pass a minimum % to be displayed)

3. The keywords used and the audiences the ad buyer has targeted

Ultimately, it comes down the audience, and not the content. Ad buyers want their ads to be seen by "people who like X", and not "people who are currently viewing a video/web page about X".

There isn't really a way to target an ad for a specific NYTimes page for instance, because they cover a variety of topics, and multiple stories are published each day. To be more precise, there are ways, but the economics of that probably wouldn't be in favour of the ad seller.

It is possible to do this for YT channels, as they tend to be more focused; MKBHD stuff will always be tech or gadget-focused for example.

We still do, it's called native advertising and it's a HUGE market.