Rich people generally don't keep the majority of their money as cash in a vault. When money lies in the bank, the bank invests it in the real world. Or more directly, when money lies in stocks and bonds, it is invested in the real world.
Is it though? How much did Nvidia invest more, after their stock hikes? How about Tesla, Microsoft, Apple? No. They cut their staff or maybe stayed at their current investment levels.
So the question you should be asking is: How much did Nvidia invest before their stock hikes? And which companies will the original investors fund next after selling their shares at a profit?