The C150 driver will in those 1500 hours experienced shaking knees and dry mouth at least several times because of circumstances that arose unexpectdly such as, weather, mechanical, fuel concern, lost, etc. These things matter and are lessons that will never be forgotten.. I could go on about the importance of time in the saddle and how successful aviating is a continuous chain of decision making where the wrong decision could cost you your life. SIM world is wonderful but you will never kill yourself therefore you will never make life/death decisions.
Yes.
As an owner of a C150, with more than 3000 hours flying it, I was getting complacent. So I went for my helicopter license. I knew a lot about being in the sky already, but those first few solo flights in the helicopter reminded me - it's all me, no one here to fix it if I get it wrong, I am solely responsible for
everything which will make this flight safe. The basic fear of getting it wrong makes one a better pilot, that fear over and over makes one better yet, even if those decisions are made while flying a lowly C150! Sure, experience should be had on multiple types, as many as possible, in varying circumstances, I'm not advocating 1000 hour in the circuit in a C150. But, hours of mundane experience flying something, solo, for real, where your decisions have absolute meaning, and you learn from the fear of the real risk of getting it wrong. Then.... you're ready to be a crew member.