I think it's powerful when used correctly.
For example, consider Discovery ads. A user is browsing youtube and then decides they want to search up "how to clean out my garage". Your video shows up as first because, well, you paid for it.
You, a garage connoisseur offer multiple videos on your channel on how to truly pimp out your garage. (stay with me I know this isn't the best example) This user sifts through the countless videos you offer and eventually subscribes. Meanwhile while you continue to pump out content you offer a course or private garage coaching sessions or maybe merchandise, etc.
Eventually the user that you paid for decides that he wants to buy your course because you've already provided him with so much that you never even had to sell him.