Lol yeah the gyrobus and its lesser-known younger brother, the General Electric Battle Top. Here's the problem: GE's clever idea was to dissipate 1.5 tons spinning at 10,000 RPM through explosive disintegration. That's 373 kJ of bad news. A couple pounds of TNT is 4200 kJ worth of bad news so converting your spinning war top of doom into explosive force, without conversion, is a quarter stick of dynamite. More or less. Work with me here. Spinlaunch, on the other hand, is at about 800,000 kJ assuming the arm that's flinging it has no mass. Assume we're just talking about the counterbalance - we get to dissipate the energy of one of these in our hypercentrifuge every time we fire it up. Again, assuming unicorns and rainbows, massless masses, perfect conversion, la la la la la. They'll want to move the office methinks.
Funny, I didn't even know about the GyroBus! The one I was thinking of was in the 2000's, and I can't find a link to it any more. I think the City of Seattle was looking into them, when I was with the Pioneer Square Community Association. Seems like we saw a presentation on this possible technology being used in Seattle transit buses. Google told me about this older Williams Racing project which used a flywheel as a power-assist in traditional ICE-powered vehicles, too: