You are extremely, even naively optimistic. The gap between what you understand under the term democracy and what is "Russian democracy" is several times bigger than the difference between Russia's and N.Korea's "democracies".
You're the only one using the term "democracy".
Even under an authoritarian dictatorship without any pretense of democracy, the consent (or at least acquiescence) of the populace is necessary for the dictator to rule. Civilians far outnumber the rulers, after all, or even the military. Even if the entire Russian military sided with Putin—and against their own friends and relatives—there is no way he could stay in power in the face of a mass civilian uprising.
And even in the worst dictatorships, mass public protests will almost always lead to the regime being toppled (perhaps only to be replaced by a worse regime, unfortunately, but still toppled). The population of any country is simply too huge to completely ignore, if it turns against the regime en masse.
If you don't believe any of this, then tell me - why do you think Russia is investing so much resources in internal propaganda? Why are they pretending to hold free elections? Why does Putin pretend he has a noble goal in Ukraine? It's certainly not fooling world leaders, so if his own population can't do anything about it, why even bother?