Its nice to win it, but hardly heartbreaking if you dont. Same as charity shield, and super cup.
Losing an FA cup final, or the 2 big European ones, even EFL cup to an extent (for clubs like Soton etc), can be gutting and really heartbreaking. I would 100% rather lose to Mamelodi Sundowns in the CWC, than not win the FA Cup.
You ask any Spurs fan, Arsenal fan, City fan, chelsea fan, Liverpool fan how much theyd like to see their side win the CWC,,, wont be many fans
and also the "Best club in the world" for winning CWC, is not an official title, its just an opinion.