What stops Linden Lab from doing something so horrible to the grid, such as raising L$ prices and land prices, forcibly all but closing the grid?
Knowledge, the knowledge that if they do so people will leave, and take their cash with them, and SL will tank. It is this knowledge that prevents them from just pulling the plug and doing anything that would be extremely drastic (if you think age verification or voice came on suddenly, you haven't seen what it could have been like).
This is a pretty powerful weapon. They must tip toe around this, because it will occur if they impose something large on the grid. How do you work around this?
You do it in increments, you make sure that once one feature causes a hailstorm you wait until it calms before you unleash the next. They are building an anthill one grain at a time, so you don't immediately notice it and exterminate them. Small, baby steps is the path they are taking.
You must realize that I am not saying their method guarantees happiness in their customers. It is merely a way to damage control during feature implementation while retaining a large enough user base to provide a profit. It is a genius work-a-round, which completely neutralizes our main weapon against them with regards to preventing undesirable features (which can include whatever, the purpose here isn't to analyze each feature that's shaken up the land). It is genius because people get bored of fighting for a cause. You may lose one or two Wayfinder Wishbringers, or a James Gill, but on the whole you retain a large user base. User satisfaction isn't a concern, as long as the crap storm remains low level enough.
The best analogy I can think of it starting fires in a vulnerable forest in order to prevent a firestorm years later. It's shear brilliance in action. There is no way to counter this, save for a massive coordination of all the residents and keep them annoyed enough that Linden Lab would feel the heat, and we'd have to be deadly serious in our threats to leave SL. Half the grid tiering down would send a warning shot across their bow.
The problem is that organizing this would be similar to trying to herd cats. Linden Lab knows this. That is why their method of operating a feature inclusion is genius. They introduce voice, it starts a firestorm, it dies down. Then they add identity verification, it starts a firestorm, then it dies down. There is never a summation to trigger any action.
Which is why, nowadays, I laugh more often when people do things like "Write an Open Letter to LL about Canadian Laws Against Age Verification" or "Take back the grid" (I'm not linking to the blogs and forums behind these headlines to save your brain cells. I already read the back story and I am dumber for having done so). I laugh because in a month or two, it will all be forgotten. And then they'll roll out Windlight (and who knows what else), and we'll all get in a bunch again. And again.
I plan on not caring anymore. I'll just watch the world rolling restart by from the comfort of where ever I happen to be at the moment when I teleport to get around the restart.