This article isn’t really addressing the mechanism for punishment, just the reasons why we do it. Like, whether it’s a couple of brothers or a taxpayer funded bureaucratic prison system, if we’re punishing someone just because we think they deserve it it’s retribution.
Beyond that, I feel like what you just described is actually just a step backwards from where we’re at currently. Like, why should people who aren’t privileged enough to have brothers not get the same kind of justice as people who do?