In principle, a meer post on nostr about cyberspace is "advertising something" to the people on nostr and those it reaches.
Discussion
Yes. This is more of a referral than full on surveillance capitalism. The digital advertising apparatus will be rendered useless
Digital advertising doesn't work. That's why places like FB etc started paying users to become influencers to sell their products etc.
Old school methods work best:
Word of mouth
Door to door
Billboards
Flyers under windshield wipers
Etc
This is how you reach people in today's world without getting skipped over and people can't pay to remove either.
As someone who worked at an ad agency for 16 years, I would disagree with your assertion that digital advertising doesn't work. I've seen it work. But I understand what you are saying about the value of IRL ads and I agree that they are powerful and will always be around.