I guess that’s one way of thinking about income redistribution, but I don’t think it’s a robust way to analyze it.
In a competitive market with low switching costs, workers get paid roughly what their work is worth. It’s government’s function to ensure the market is competitive and the switching costs are low.
But a competitive market with low switching costs does not guarantee that every worker is capable of performing at the median in terms of value creation. In fact it’s a mathematical impossibility.
So in perfectly competitive market with a progressive taxation model, lower income earners will be subsidized by the higher income earners, despite everyone being paid entirely competitive and appropriate wages for their individual contributions.
It’s not the employers responsibility to subsidize below-median earners, because they aren’t the ones collecting the surplus from the above-median earners.
I personally think that most of these subsidies shouldn’t ever phase out, specifically because they screw over the middle class with punitive marginal tax rates. The net effect is that you still cross from negative to positive effective taxes at some point, but it happens with a much smoother marginal tax rate versus gross income.
A completely different discussion is whether employers should be able to hire very low skilled workers to do menial jobs at very low pay, or whether we should force employers to provide training and support to employees to the point where they can perform enough valuable work to justify some minimum wage, and everything else just needs to be automated away.