Similarly my friend swaps electric cars every couple of years (Volt -> Bolt -> Equinox) bragging about all the discounts and subsidies he's gotten. Maybe it's still beneficial through the used car market but it doesn't feel like an effective subsidy for the government to be handing out.
it's a way to get infrastructure built up. the tax dollars pay for bootstrapping of the ecosystem. it's actually smart in principle if you think about it, but obviously there's room for abuse and outright fraud.