Why is a 1550 gold item stronger than a summoner spell?

** Quicksilver Sash**

• +1550 Gold
• +90 second cooldown (shorter than most Suppression ult cooldowns)
• +Removes DOT, Attack Speed Reductions, Defense Shredding, Grievous Wounds, and Suppression, which Cleanse does not.

Cleanse

• -Summoner spell (??? Gold Cost)
• -210 second cooldown
• -Does not remove DOT, Attack Speed Reductions, Defense Shredding, Grievous Wounds, and Suppression.
• +Gives 65% Crowd Control Reduction for 3 seconds after use.

This doesn't make any sense. Aren't summoner spells of higher value to players than in-game items? Why would an item completely outdo a spell, on a lower cooldown, only cost 1550 gold? In essence, Cleanse only has one positive point over QSS, and that's the 65% reduced CCR.

I think the debuff removal effects should be switched. Essentially, if you get 1550 gold in a game, you can counter an entire champion and not even have to worry about using the item at the right time, because the cooldown is so short.

So TLDR: Either double QSS cooldown time, or switch the debuff removals. When you're playing mid lane against Zed, grabbing Exhaust is a good idea to reduce his damage when he goes all in. The same should be true of playing against Suppression champions.