Even in the winter when it's quite cold and dark, Stockholm is quite walkable. It helps that its archipelago nature means it doesn't get as much snow as inland. But the ferries and public transport work really well.
There seems to be a growing trend of talking up Stockholm (maybe because of the insane housing market), while not much have happened really. Most of the "ideal" development of Stockholm seems to be from pre-'90s, including all but one subway station.
In the last 30 years the main developments have been malls and "soulless" residential areas in the spirit of "Hammarby Sjöstad". [https://en.wikipedia.org/wiki/Hammarby_Sj%C3%B6stad].
But indeed I assume the Stockholm Tourism authority appears to be doing its job well at the moment.