If exemptions were only granted for individual events in the Olympics and Asian Games, the problem would be solved

Whether it's Yang Min-hyeok or anyone else, the reason people talk about "exemption buses" is because the real issue is that those who contributed 0.05 or 0.03 gold medals are receiving military exemptions.
In the case of individual events where the person brings home a total of 1 gold medal (I'll be generous and include doubles), they should receive the same benefits, and all other exemptions should be abolished. Alternatively, they should have to win medals in three or more competitions.
The arts sector should also follow a similar rule to the Olympics and Asian Games, where benefits are only granted for winning one or two specific competitions per field (for piano, at the Chopin Competition level), but large-scale group exemptions like orchestras should not be allowed, and domestic competitions should not count, etc.