So those accumulating the wealth, don't provide opportunity for others to do the same? Do they generate all the income themselves?
My on view on trickle down may not be the same as your definition above, but for me, it gives opportunities that otherwise wouldn't be there. What people do with the opportunity is on them. We should absolutely have equality of opportunity, we should not have equality of outcome, to argue equality of outcome will dis-incentivise the innovators and entrepreneurs from creating opportunities in the first place.