A USB-A device obviously wouldn’t have been designed for anything more than 5V. But anything with a USB-C socket is living in a world where a faulty source could accidentally give it a higher voltage. At that point it’s just about your tolerance for risk - maybe for something worth $100 or less and not supporting PD you can skip out and if there’s a faulty charger that blows it up then whatever, but for something selling for a few hundred dollars (like the Switch, or phones, etc.) it’s worth the 50c in BOM cost for the extra protection…