you actually have the wrong idea then. You would want to in fact, increase your media presence 10-20x. Paying people to maintain false accounts with various real & fake pictures of yourself claiming residence in places you have lived or traveled. These large active social media accounts will provide a haystack buffer for your real account which you will gradually provatize and hide.

Generally what you are asking for is not currently possible. You can make requests of search engines to not show links, you can send DMCA takedown requests to places that have photos, and you can plead with forum mods to delete your posts. You can ask the Internet Archive to delete pages about you.

But none of that protects you when some kid who made a copy of things and posts them again and again on some random forum site like one of the chan sites or some other home grown forum. Eventually it will be indexed again and you'll be back trying to whack it out of existence. Sorry.

Yep, as mentioned above, often "chaffing" is a more realistic approach. Sowing confusion is easier than refuting or censoring.

Often you can't take back what you said, BUT you can change e.g a non archived profile image to associate comments with a fake account.

Related question: is it best to give a child a unique, or very generic name?

Currently I lean towards generic, as unique names or pseudonyms can be created on demand.

All of this intersects in interesting ways with "real name" policies IMHO

This was sort of the plot of the Orson Welles film "Mr. Arkadin" (aka "Confidential Report").