1) Lightning is USB2 only. USB-C supports USB3/4 and DisplayPort, which have much higher signal integrity requirements which the Lightning connector wouldn't be

1) Lightning is USB2 only. USB-C supports USB3/4 and DisplayPort, which have much higher signal integrity requirements which the Lightning connector wouldn't be able to meet. 2) Lightning is relatively limited in its power handling. USB-C handles up to 120W (!) -- if you tried pushing that much current through the little contacts in Lightning, the connector would melt.