I'm Hungarian BTW. And you seem to misunderstand me. I'm not saying that teens yearn for Kádár or much less Rákosi. I'm saying that the Che t shirt and the rest of the "Western teen rebel starter pack" are parts of a cool identity, it's not associated in their minds with historical Hungarian communism that actually happened.
It is a continuation of a historic West-imitation that's as old as taking on Roman Catholicism or adopting the Renaissance in Matthias Corvinus' court.
Hungarians in the 80s didn't long for some different philosophical organization of society. They wanted the cool Western things, good home appliances, higher salaries, vacations abroad, jeans, shoes, porn magazines, Western pop rock punk music, Coca Cola, McDonald's etc.
So shortly after the change of system in 1989 edgier kids also started to adopt the teen rebel fashion including Che. Just like there were a few goths and emo kids in every class later on. And today it's kpop and whatever is trending on tiktok.
Western Kids larp communism so eastern kids larp the larp. Its not unlike importing Buddhism and mindfulness from California. People adopt it because it is cool in the West and adopt the western interpretation of it.
Imagine if a hip Indian tech worker in Bangalore adopts Californian Buddhism. It would not be because of the local history of Buddhism, but the coolness factor put on it by Silicon Valley. It's like when pizza was backimported to all of Italy, after it got popular in America, even though it was a much more local thing in a small part of Italy before.