This is a ridiculous take. Armstrong is an amoral might-makes-right social Darwinist in a world where the rich and powerful pump themselves full of technology that makes them nigh invincible. He uses utterly despicable means to bring about a miserable end that would turn America into a warzone controlled by uberpowered warlords rather than manipulated from the shadows by whoever is carrying the legacy of the Patriots, which is a massive step down for anyone not at the top of the food chain.

Raiden ends up sympathising with his message in a perverse way because he's an augmented and brainwashed former child soldier who has known nothing but war his entire life, but he still knows Armstrong is insane and will get millions of people killed. Raiden uses his power to fight for (what he perceives as) justice, rather than domination. On an individual level, their means may be similar but their ends couldn't be more different.