I have probably already left (consciously or not) enough info on the internet, for data scrapers/AI tools/whatever to probably know me better than myself, and that's probably true for any person that have ever used internet.

Knowing you? Possibly. The second half of your claim is unsubstantiated.

Websites might know specific aspects of how you use the internet, for example, what times you use that site. This is just information you yourself haven't cared enough to log and examine. It isn't extraordinary.

To extrapolate that to "Better than I know myself" is paranoia.