Agree on all, but more planet friendly than what? Than they are or than the alternative?
Where "we" are.
On just the claimed higher power density this brings the potential for a whole host of planet benefits spinning out of the lower mass of "stuff".
The raw material to be mined, for the batteries, the vehicle's structural requirements, tyre scantlings, plus all the logistic needs related to shifting and processing less stuff.
Along with the lighter vehicles [like for like] less trye wear, less plastic pollution from tyre wear, less demands to knock down and rebuild multistory car parks as EV masses move nearer in weight to the present ICE vehicles.
Here I am assuming the above are not off set by challenges in "gleaning" sulphur and iodine based raw material, but both are available respectively from volcanic activities, and the sea. And also assuming the demands on any needed trace elements will not become an additional issue.
On the face of it the planet could well benefit, though cheaper EV vehicles might in itself have more of the world's population into vehicle ownership!