It's not that hard for a new idea to look good for a couple short months/years. Building an ongoing, self-sustaining society that doesn't go completely off the rails is a whole other thing. There's a reason all these idyllic examples people give (Catalonia, Pre-USSR Ukrainian socialism, Paris Commune) were short-lived. If the Bolshevist revolution had been quashed in 1919, it would be idealized today.