I get your point: quality over quantity. For me a growing process should have 3 steps: acquisition, education and loyalty.

With acquisition you can focus into spreading the word as much as you can and bring lots of users from everywhere, maximalists, shitcoiners, etc to join and try the platform.

With education you must focus on make the acquired users to understand you and your goals, what your product is (in depth), what they can do, what they can earn, why is the tool suitable for their needs, secret tips on hidden and less known features your platform has, what sets your product apart from closest competitors, etc, and a loooong etc.

With loyalty then you prove your educated users´ patience to see if they can prove valuable to you as much as you are valuable to them.

If you can keep 10% (ex. 5K users from 50K initial acquired users) without spending way beyond the funds you allocated for a given campaign i´d say is a win after all.

Each platform should have it´s goals and i think SN should define its own growth plan focusing in such goals (if defined ofc).