Agree.
I see no need for TB3 over TB2 on the MBA, and there isn't much out there that that even challenges TB2. Apple still needs ways to differentiate their ranges, and frankly it's adding more cost that could be better spent on the MBA screen. Don't give Apple ideas for more useless updates
Also I have yet to to see any devices using USB-C in the wild. USB3 with dongles will cover for USB-C for a while longer. USB-C is definitely the way forward but the MBA doesn't need it yet.
USB-C also, in Apple's mind, means getting rid of the magnetic charger. Three times today alone my kids have tripped over the charger wire. I'd have three smashed laptops (or the same one smashed three times) if it wasn't for the magnetic charger.