We are not talking about 1 or 2 companies this is the KOSPI similar to S&P in US. This worse than 2008 for Korea. Additionally many Koreans use leverage which means they were margin called and some are even in debt now.

The collapse surpasses the October 1997 IMF crisis, when the index lost 27%, and the October 2008 global financial crisis at 23%.

https://finance.yahoo.com/markets/stocks/articles/south-korea-stock-market-crash-092957385.html

To fix the situation the government intervened and poured NT$450 Billion investment into AI.

https://finance.biggo.com/news/b4b67689-a989-445f-810c-9cb92bca140f