Earlier quoted context omitted.
> Now, what additional personal data are collected by tracking pixels? If I read it, when I read it, where I read it from (location, device, etc)
None of these are personal data if not liked to the email address, which they do not have to. If linked to email address and considered personal data then the argument is what is covered by consent to receive email marketing? IMHO tracking whether the email was opened is covered (in the same way as agreeing to receive phone marketing should imply they can track whether you answered the phone...). They will also obvio…
But agreeing to receive a snail mail does not imply consent to track if it was read. I feel that email is closer to that.