Eh, the Falcon Heavy (the pending replacement for the Falcon 9 whenever he can get them to stop blowing up) is the exact same concept, but less functional.
A partially reusable centre portion (the Falcon 9 itself is partially reusable, only stage 1) with disposable rockets providing the additional lift it needs to carry payloads that the shuttle was carrying 40 years ago.
Sure though, SpaceX flights are 10% the cost of shuttle flights. But they're far, far less versatile. The Falcon Heavy isn't rated for carrying humans (and SpaceX isn't trying to get that rating). Also much smaller payload and no capability to do much of anything but ferry satelites into orbit (and while the Falcon 9 is active, astronauts to the ISS that wouldn't have been possible without the shuttle).
It's easy to blame the shuttle for the deaths of the astronauts but it's not really true. Challenger was destroyed when the rocket booster blew up, which was determined to be a faulty o-ring. Nasa cheaped out on procurement there, it had nothing to do with the tech of the shuttle itself. Columbia was damaged in flight, NASA knews about the damage and refused to wait for the DOD to task a spy satelite to get a better look at it, instead decided to risk re-entry with a hole of relatively unknown severity in the wing.
NASA killed 14 astronauts with shitty safety practices, not the shuttle.
Most of the shuttle's systems were designed in the 70's, could you imagine if they had never stopped developing better and better tech? We're as far removed from the design of the space shuttle as the space shuttle was from the roaring fucking 20's, prohibition, Al Capone, etc and tech has grown far faster between the 70's and now, than the 20's to the 70's. As for the cost, the total cost of the shuttle program was somewhere in the 500 billion dollar range over the course of decades, or 1/5th of the stated costs (not including VA stuff for decades) of the war in Afghanistan, 1/4 the Iraq war, etc.
