Too many people believe the following, unqualified:

Anyone who thinks that you can have infinite growth in a finite environment is either a madman or an economist. - David Attenborough

In fact, there will be near infinite growth until life is extinguished once and for all some dark day in the distant future. That is to say that life is growth. Homeostasis is quite another thing and does not preclude growth, but rather the growth and then death of lifeforms.

I don't think you're disagreeing with what Attenborough is saying. Injecting new people, or more work by existing people (such as publishing new content on Steemit) is exactly a non-finite situation, so to speak. Though yes, either you grow, or decline, in systems such as this. There's never real homeostasis.

And I agree to some degree. People come to a system. They accept it. But as time goes on, they grow dissatisfies. This is normal.

Now they can either leave, or try to change the system. The thing is, too often people don't realize they can't change the systems, such as coming to a subreddit, or a privately-controlled company, and telling them how to do their stuff. The people running the place don't have to listen.

Steemit purports to be the sort of place you can bring change to, but the entrenched players can always block it, so not really.

Now, I want to question you on one thing you say:

I think the writing is on the wall now, and has been for a while. Steem can still be something really world class, but it has failed to deliver on many fronts. I don't say that Steemit have failed to deliver (though they have) but that Steem has. And that's on all of us.

I think of "Steem" as the coin, and "Steemit" as the blockchain and the community. I think Steemit is what failed us, not "Steem." The coin is just there, as another coin. It's this so-called social-network platform, and as you point out, parts of the community, that failed, no?