As long as your roo is a well-mannered gentleman, there's little reason to remove his spurs. However, there have been rare instances where a rooster has injured himself by falling off a perch onto his spurs, impaling himself. More often, but still rare, a roo can injure a hen while mating if his spurs are so long they puncture the hen's sides. These injuries are often life-threatening.
Removing a rooster's spurs is nothing like declawing a cat. Apples and oranges - false-equivalency. A roosters' spurs are made of the same thing your finger and toe-nails are, and have no sensory capabilities. You can remove or cut off the tips of the spurs without any pain to the roo.
I prefer the removal of spurs as a matter of flock management, myself. I take a pliers and grasp the spur at the base and twist very gently back an forth until they loosen. Then very gently, with your fingers, twist until they lift off. I just read about the "hot potato method" and it gets rave reviews since it loosens the spur without the twisting. You microwave two potatoes, one for each spur, place the soft, hot potato onto the spur, leave for a couple minutes, careful the hot potato doesn't touch his leg, remove, and the spur should lift right off. Put some Bag Balm or bacterial ointment on the fleshy nub, and it'll heal and harden in a day or two. It'll grow back ever so slowly, but you may want to do this again in a year or two when they grow back.
If you go for the filing down or cutting of the spur, you run the risk of major bleeding if you cut too close to the "quick" or fleshy inner spur. It's like trimming your dog or cat's nails.
It's entirely up to you how you deal with the spur issue. But bottom line is, it won't hurt your roo. But it does remove a valuable weapon for protecting the flock. You decide if the trade-off is worth it to you.