>makes the human race seem quite easily hackable.

If the human race were not hackable then society would not exist, we'd be the unchanging crocodiles of the last few hundred million years.

Have you ever found yourself speaking a meme? Had a catchy toon repeating in your head? Started spouting nation state level propaganda? Found yourself in crowd trying to burn a witch at the stake?

Hacking the flow of human thought isn't that hard, especially across populations. Hacking any one particular humans thoughts is harder unless you have a lot of information on them.