I agree with you with regards to public postings made by us being a matter of public and permanent record - no problem with that, its our choice to post in a public forum. Personally I think open and public debate and discussion is good for society - and not everyone in world has this luxury unfortunately.If I/you/we make post on a public forum, you've already made the decision to permanently share.
My OcUK postings can be used to influence elections?! God damn I knew I was some hot ****.
As in individual - this kind of thing makes very little difference I agree, but in a small way yes, your browsing habits may have made there way into someone’s data set...
When you've got this data for millions of individuals across hundreds of thousands of websites it could be an incredibly powerful tool, that tool could be used for good, or bad - but that's something that "we" can't influence or control - the only influence or control we have is to deny access to the data in the first place IF we disagree with how that data ends up being used.