In Europe where Football is actually huge, stadiums are used for concerts too. So I don’t know what makes SK so special. Some tools exist.
Building another stadium is a waste of space, money and is not environmentally friendly.
The different is technology and cost. The post also the cost of maintenance. Stadium in europe usually cover the grass or remove the grass if the stadium idle from football match.
Special stadium like real madrid can just replace the pitch.
This LYW concert is special case since the national team got match in June and want protect the grass. Usually no concert allowed if match soon happen