That statement is true, but they have been giving these credits to Prius owners for years. The 4Xe can run solely on the battery.............so the title for an EV vehicle can be subjective.4xe is not an EV, though. Despite the cord, it is a hybrid.
"Plug-in electricdrive motor vehicles (sec. 30D) Four-wheeled vehicles (excluding low speed vehicles and vehicles weighing 14,000 or more) propelled by a battery with at least 4 kilowatt-hours of electricity that can be charged from an external source
Base credit of $2,500, plus $417 for each kilowatt-hour of additional battery capacity in excess of 4 kilowatt-hours (up to $5,000) for a maximum combined credit of up to $7,500
200,000 vehicles per manufacturer limitation"