Yup there's no alternative being offered to the current economic arrangement, the parties offer different brands of neoliberalism. Democrats want to ensure everyone can be included in this system, or at least the idea that everyone can. You get this in things like Kamala's "authentically me" videos or the tax incentives, just work hard and you'll succeed. Republicans offer a more fashy brand of it with the socially reactionary pandering but economically they generally pass bland neoliberal shit with extra loosening of regulations. Like Biden's biggest legislative victory is probably the CPA/Consumer Protection Act which restricted conditions people could file chapter 11, this benefits the debt holders ie credit card companies at the expense of making sure less people can escape their debts.

I think the "kids in cages" issue highlights how these things are processed by these politics. That treatment of immigrants is a byproducts of this neoliberal capitalist structure, people know it's wrong and use these politics as a way to morally absolve themselves when opportunities arise. Democrats being in power doesn't change the kids in cages, if anything climate change and mass migration will only get worse, however now it's not politically convenient for the kids in cages to be an issue. The result is it continues and people wash their hands clean by pointing to the other neoliberal faction as the source of the blame, when the issue is the system itself and having no alternative option.