"Trickle down" was an unfortunate term to be coined because it triggers an image different than Reagan intended. Reagan, as all supply sider capitalists know, knew that poor people don't create jobs. Only successful, prosperous people create jobs. And since it is mostly successful, prosperous people who are the rich, that translates to:
It is necessary for people to become rich in order for there to be jobs available to the poor.
And once you start creating jobs for the poor, the prosperity doesn't 'trickle down'. It 'bubbles up'. Put 10 million people to work in permanent jobs who aren't working now and you have 10 million new consumers who will increase activity to produce the consumed good and soon 10 million more are at work. And it continues to 'bubble up' from there. And all those new taxpayers who are paying into instead of draining the system will start bringing down the deficits. If we do it well enough, we'll eliminate the deficits and start bringing down the debt.
Cutting the capital gains tax; making the Bush tax rates permanent for another decade or so, etc. will spur the 'rich' to take the risk to get back to work and hire those first 10 million or more permanent workers. History has proved that this works time and again.
We aren't saying eliminate all taxes. That would be stupid. But we can eliminate all the government doesn't absolutely have to have and let a growing economy and GDP do its work.
It does require the political class to accept a smaller instead of ever increasing government. And it does require the elite class envy group to understand that a rising tide lifts all boats, even those of the rich.