An autocratic country could easily spread propaganda in the democratic country, because of “free speech” rules that most democratic countries have, but a democratic country cannot easily spread its propaganda in the autocratic country.
An autocratic country can buy an election in the democratic country, but the democratic country cannot easily coup an autocratic country.
Are all democracies are doomed to fail?
Is the future of humanity, autocracy? For the rest of humanity’s existence?
Autocratic countries have a small number of leaders, often one.
The goal of said leader isn’t really to grow and bring wealth and prosperity, but to never lose power.
So overall, the economics of the country would plateau, cause why risk allowing wealth to grow and fall into your opponents’ hands?
Hence why countries like Russia and North Korea rarely innovate, but just take what’s available to further entrench their country’s position.
So the only way autocracy can prevail is by brining down anything superior to it, much like what Russia is doing to the US.