1. Who is Jožef Pučnik - hi is guy who died few years ago and he was politician (interesting that he was closer to political option that is now in rule). Rename Airport just becasue of that - no. Pučnik was also very important person who had great impact on the way of Slovenian independence process and so on - just see wikipedia if you are interested. And this is official reason to rename the airport.
2. What does this mean in reality - we name streets, roads, buildings and other things by important persons. In communist times lot of towns and streets were named by war heroes and important events during the second World War. After proclaiming independence most of these names were changed. So we had Titovo Velenje (Titos' Velenje) - now it is only Velenje (despit town was really almost created by communist regime and Tito as leader). Than we had Tito's street in center of Ljubljana - Part of it is now called Slovenska(Slovenian) Street, other part is now Dunajska (Wien) street. And so on and so on I was attending primary school of national hero Matija Blejc - Matevž and it is now only Primary school Mengeš (how unimportant).
And we still do not have some streets of Ivan Kramberger(there are two but in the way that they could be named aslo by some other Kramberger), who was murdered 15 years ago. And he was important humanst in Slovenia and also man who also made great improvement of aparat for kidny dyalise (sorry if I spelled wrong) and so he helped much more people to better future than Pučnik.
3. Conclusion about renaming airport - we are renaming something by some guy who was important for Slovenian history, like in communist times. And on the other hand we are denying par of our history by renaming communist titles to more neutral one (Velenje should stay Titovo). We can just wait that we will get streets named by current prime minister or maybe even minister of finances or even minister of foreign affairs who is holding this position since Slovenian independence and who never finished single term on this position.
It could be much better to create special Fund of Jožef Pučnik that could promote Slovenian national identity by buying Slovenian flags for each houshold form this fund or rewarding researchers and students who are dealing with Slovenian identity or so. And not not some shitty Airport where nobody will even notice that name. And if you are renaming in Slovenia you have some Slovenes who are important for development of aviation - like Edvart Rusjan (according to wikipedia at his funeral there were 14.000 people who recognised his importance for developing aviation). But it will not happen.