All that goes up must come down. SK is one of the top 10 economies in the world, despite the fact that in 1950, PHL aided Korea. They were very poor. But leadership will and the little help from USA made SK an economic powerhouse.
However this video thinks SK is stagnating. Coming from both internal and external factors. External factors: slow down in world economy, threat or war, the Covid pandemic, energy problem.
Internally, it is because of complacency of Chaebol management which are now in 2nd and 3rd generation management and leadership. As they say, first generation builds it, second generation spends and enjoys it, the third generation runs the enterprise to the ground
We wish Korea well and all the best