The final few years of Park's rule was really repressive. He was of the opinion that nobody else could push S. Korea forward except him.
In recent years after the whole nation suffering from economic crisis and various interest groups fighting for their own narrow interests, people are feeling that the country is not moving forward as it used to. Many Koreans became nostalgic for the sense of direction the country used to have under Park Chung-hee. For all controversies, his drive for economic development is now generally viewed in positive light. As a result, Park's standing has improved recently.
His reputation is rebounding mostly because his erstwhile political enemies are screwing up S. Korea. Kim Young-sam, Kim Dae-jung created their share of messes. Now a whole cadre of dissident activists under him and his successor Chun Doo-hwan got hold of power. To me, they are doing no better than the two Kim's, and probably worse given time.
All these democracy activists make the former military strongman look better by their incompetence. And that is the real tragedy. People trapped in their confrontation mode during late 70's and 80's against the military regime bring the same mindset into governing 21 century S. Korea. Hence, the reflexive sympathy toward N. Korea and hostility against America because that is the polar opposite of military regime's policy, anti-communist and pro-American. They also want to set up 70's style welfare state in S. Korea, which is now going out of fashion even in Europe.
This reminds me of Russia immediately after Soviet breakup. All naive idealists, intellectuals, and unscrupulous opportunists, and corrupt criminals came out and claim to be champions of human rights, freedom, and free enterprise. The net result, however, is the nation mired in prolonged chaos, poverty, and lawlessness. This made old Soviet KGB look good in comparison, even though KGB was the most reviled institution toward the end of Soviet era. Now, former KGB men are in charge of whole Russian government and running it. However, no real resistance to de-facto rule of KGB brotherhood. On the contrary, Putin and his men are popular.
The only difference is that Russia had an reckless rightward surge while S. Korea could have the reckless leftward surge. Before the correction kicks in, many lives will be broken and astronomical amount of wealth may be destroyed, unfortunately. That is what Russia's recent past and S. Korea's immediate future may have in common.