Trickle down has to be one of the most discredited of all neoliberal ideas. The claim is simple. It is that if the rich get richer then their spending will pull everyone along behind them as their wealth trickles down via their spending.
No, it ain’t. It’s that greater investment by the richer among us (this being the flip side of the obviously true greater marginal propensity to spend of the poor) creates a wealthier society over time.