It's literally exactly as fast as lightning is for the current generation phones.. so you lose nothing / gain nothing.
But I guess it's apple so we gotta riot while it's perfeCtly fine for android phones to ship that way depending on which vendor you pick.
That's a good point though the port is also needed to pair an iPhone or iPad to a Mac/PC (the famous 'Trust This Device' screen can only be triggered if a device tries to access the phones data via USB) which is required to do any backups / music or picture syncs in the first place. ,nd it's also necessary if youre a developer as - even at USB2.0 speeds that people complain about here - it is still faster to test and debug applications than via wireless.