You say "aggressive attempt to extract value," and I say that if they are the legal landowners, they have every right to do so. If they're not... less so.
"Ownership of a piece of land" is an entirely different notion from "ownership of a piece of land that the proponent assumes carries full redevelopment potential", but you're assuming the latter is automatically the case in any instance where the former has occurred.
If a proponent makes an aggressive assumption of the value of a site it has purchased based on what it thinks it can achieve from an approvals perspective, that's on them. The City's mandate is not -- and should not be -- to ensure it unlocks value for speculative projects; its mandate should be to deliver the best outcomes for its citizens while doing so within a reasonable frame that allows for the efficient operation of the private economy. No aspect of the City's actions in this process have made me think that they are falling down on the second part of that responsibility.