Lean Startup Revolutionized Product Management?
Question: "Hasn't lean startup revolutionized product management?"
According to PMTK, lean startup is wholly unrelated to product management.
The Lean Startup is a largely unproven theory which advocates iterative development (e.g. Agile) and frequent incremental product releases; as opposed to engaging in preliminary, thorough and systematic market research that is followed by a phased and pre-planned product development cycle.
The general premise in experimental discovery-driven approaches is that on-going customer feedback continually helps test the market's receptiveness to the product and its features and quickly allow for any required corrections to marketing activities and product development efforts.
The main limitations are that discovery-driven approaches do not scale well which renders them not fitting for large and complex projects and products, they depend on fluctuating and possibly inconsistent customer feedback which makes the product susceptible to erratic shifts in concept and feature scope (excessive pivoting), can be quite costly if many scoping and architecture corrections are merited, and they do not provide sufficient and reliable information for making sound strategic decisions.
For more information, see the Blackblot PMTK Book: Second Edition.