If I can read Putin's mind, if you're a respected leader, your citizens will probably be ready to let you stay in power, and in the event of an attack, to die for you, but if you're a corrupt grifting piece of shit, then, first the walls to your bedroom better be thick, next would be the walls to the Kremlin, and finally the walls around your country's borders, and then even beyond.
My guess is why Putin hates the "NATO sphere of influence" is that he doesn't like democracy, because democracy means his head will end up on a noose, or in the best case scenario, in prison with his wealth taken from him. But on the flip side, it's not like American or EU democracy is free of thieves and nepotism either. Special greetings to Jean-Claude Juncker and Ursula von der Leyen!