Access to education has been supported by the federal government where individual districts lagged behind more wealthy areas. Without the federal aid poor districts would be much worse off as far as education goes.
Yes the federal government has long violated rights and done terrible things. We could go on listing the atrocities committed by the feds domestically and abroad for days e.g. forced sterilization, internment camps, vietnam, iraq, residential schools and the various iffy things the intelligence community did relating to drugs and black nationalism last century. I am not arguing that federal power is universally good or that increased federal power only resulted in good things but rather that its been a net improvement. You say its impossible to determine if we have more or less rights post civil war than before but I would posit it is very clearly more.
Yeah statelessness is a cool idea in theory. Like I said an ideal to aspire to as a society. The less coercion/threat of violence we have and the more freedom and empathy we have in society the better. Its just an ideal and not something we can achieve now IMO but still something inspiring to think about in conversations about state power or otherwise.