Trickle-down happens not in the form of money, but in the form of technology and things
Trickle-down seems to happen not in the form of money, but in the form of technology or goods. It feels like the wealthy class gets cameras, then the middle class gets cameras, and then even the poverty class gets cameras. The same goes for cars, white rice, healthcare, and computers. There are various factors involved, and it doesn't directly come down in the form of money. Self-amplifying capitalism has the nature of maximizing profits, so each player wants to maximize their own share. Therefore, the players who can make a lot of profit will generally try to increase productivity and profit margins. As a result, money doesn't directly flow down to the lower levels. So where does that money go?
The money trickles down due to factors like research and development, investment in productivity increase, or increase in labor costs due to competition between companies. It flows down for those reasons. However, it doesn't significantly increase things like the expenses for dining out or traveling by the wealthy, which would then flow down to the lower levels.
On the other hand, what's more important is the "nature of maximizing the market." In order to make profits in capitalism, you need to expand the market and continue to offer new things. That's why things become cheaper and more advanced, and the market size is moving in the direction of expansion. Things that were initially exclusive to the wealthy will gradually spread and become accessible to the general public and the poor.
In other words, realistic improvements in the lives of the poverty class through trickle-down don't correct the wealth gap. Instead, it applies in the form of the poverty class being able to buy white rice at convenience stores, dress fashionably with fast fashion, take generic medicine, and have unlimited music streaming on their smartphones.
In other words, buying a smartphone and studying through the internet is the most cost-effective way to transfer the benefits from the wealthy to the people and strengthen the lower class.