Dash has decentralized technology (PoW mining, full nodes, masternodes, blockchain governance). There is no debate here.

The point you're laboring is that there's no way to prove this technology isn't operated/controlled by a handful of people. You claim that because DASH's distribution is unverifiable, it's fatally flawed as a 'cryptosystem'.

For this argument to have any substance, you should demonstrate how competing coins solve the relationship between node/coin distribution & centralization. Bitcoin for example has massive mining centralization and millions of coins held by Satoshi / persons unknown. All PoW coins face mining centralization issues at scale. Monero has a massive whale in Risto who could manipulate/trash the market at any time and arguably kill the coin. Monero's core team could arguably kill the coin if they wanted to. As for governance, explain how DASH's blockchain governance is inferior to other coins where decisions either don't get made (Bitcoin) or there are just a few individuals pulling the strings (Monero).

Basically, make some reasonable, specific arguments instead of just bleating on about the instamine.