You can't fire anything into Earth orbit. Once propulsion is complete, you are in an orbit. Orbits repeat. So if your orbit starts from the ground, your orbit will intersect the ground which is... undesirable.

Instead, you have to fire a rocket motor to alter the initial orbit into one that doesn't intersect the ground. Now you have a new problem: you have to design a rocket motor which can withstand the launch. A solid rocket almost certainly will spontaneously RUD when heavy acceleration is applied. A liquid rocket has pumps and pipes which are likely can't survive the acceleration.

This is the reason spin launch is nonsense: you've traded a solved problem (make big rocket motor) for an unsolvable problem: make a rocket motor which can withstand absurd acceleration.

The other red flag with spin launch is that genuinely new approaches to problems do not come from unqualified randos thinking about a problem. For example, if a company has a crazy new idea for blood testing, it's really bad if the crazy new idea came from someone with zero experience and zero domain knowledge.