Was Magnus Carlsen Wrong About Chess Fortresses?

After the fourth game of his 2016 world championship match versus GM Sergey Karjakin, GM Magnus Carlsen famously said, "I don't believe in fortresses!" What he probably meant is that even though fortresses do exist in chess, the majority of the positions that look like a fortress can be penetrated. Unfortunately

Chess organization will investigate cheating allegations made by world champion Magnus Carlsen

GRENKE Classic 5: Magnus wins but Levon leads

PDF) Fighting Chess with Magnus Carlsen

Magnus Carlsen's Final Fortress - Chessable Blog %

An Unmotivated Magnus Carlsen Will Give Up World Chess Title - The New York Times

Minor Pieces in Chess - Remote Chess Academy

GM Elshan Moradiabadi on the Magnus Carlsen Tour Finals

The Chess Champion's Defeat

Can somebody explain me the general concept why long castles is bad and king castles is better in this position? If it matters, i'm 1500/1550 : r/ chess

Magnus Carlsen, Ian Nepomniachtchi square off for chess crown this week - Washington Times

Magnus claims epic Magnus Carlsen Chess Tour victory

Magnus Carlsen makes history