> GDPR Twitter data export and it included me in a bunch of incorrect, non-sensical and contradictory ad targeting groups.
This is expected. It's not desirable, but it is expected.
The problem is your comparing it to an absolute. I.e. to perfect.
If advertisers had that choice, they would love it. They generally don't. Remarketing is kinda close, but limits the scale.
Rather, the only other scalable options are far worse. Think about it. What are the marketers other choices?
The one that should come to mind, and the one they spend most of their money: TV.
With TV you pick up a huge amount of waste. Say you buy a spot on Big Bang because you want people thinking of buying a new iPhone. Not a big stretch, right? At the same time thinking of all the other people they have to buy, who watch the ad, and aren't buying an iPhone. It's waste.
And that waste is huge relative to what you're talking about above.
So you're asking the wrong question here. It's not how good is the targeting in terms of precision/recall. The question is what's better?
The waste here is generally known & its priced accordingly.
> I was very disappointed that the Google and Facebook data exports don't contain this data.
It's in my Facebook export. Under "Information About You" did you uncheck "Ads"?
That's where the information is contained & it's checked by default.
You can also view it here for both FB & Google, as well as opt of both:
https://adssettings.google.com/authenticated?hl=en
https://www.facebook.com/about/basics/advertising