Now, we aren't on the receiving end of some hidden algorithm, we have a marketplace of clients and relays. Some will be exclusive with their access to certain users, or notes. Relays are gatekeepers to entire ecosystems.
With all the spam that is now quickly starting to show up, I'm assuming we're all going to gravitate towards reading only from pay-to-write or reputation-based relays? The only friction against spam is money, time wasted, or some kind of relay-side reputation score, based on write frequency, content repetition, etc.