Admittedly I've never worked at a startup. I've always taken MVPs as a releasable proof of concept. Reminiscent of the "tracer bullets" discussed int The Pragmatic Programmer.

If you're trying to prove a market, yeah, an MVP would look like the skateboard -> car image. If you're trying to prove a technology, it would look like an internal combustion engine strapped to some tires. If it was a passenger vehicle, it would look like a carriage with some engineers pulling it with ropes like horses. The "Not like this" looks like a poor implementation of "waterfall."