Seoul is so pleasant that it's impossible for it to fail

How on earth can a high-density city where one-fifth of the entire population lives
be limited to a floor area ratio of only 300% due to various regulations, making it so that even building around 49 floors
is restricted to just one or two buildings per complex because it supposedly ruins the urban aesthetic?
The building coverage ratio regulations are also high, so distances between buildings must be maintained.
On top of that, the subway system is dense, and because the country has many mountains, there is abundant greenery.
What other country's city is built to be this pleasant?
It even has the "cheat-code" level Han River, with an appropriate distribution of CBD, YBD, and GBD.
The brilliant American PhDs during the Park Chung-hee era saw the future, and now 6-lane and 8-lane roads are everywhere.
Seoul is simply too pleasant for a global major city.
This would need to break for it to decline, but as some say, everyone lives in an environment better than a resort,
so it simply cannot fall.