You definitely want to fix it, as metal panels can and will rust and or spread without a protective coating. The bumper is plastic so it won't rust but the chip can get bigger if not fixed.
Pearls are harder to match than metallics, so I recommend using the factory touch up paint for the best match. You have to shake the paint thoroughly to mix it well. Price is pretty reasonable on Amazon, and actually cheaper than the aftermarket knock-off kits.
That part is plastic, not metal. No risk of rust