Yeah, the headline and article aren’t great, and conflates fuel and propellant, but the technology is reasonable.
How is this different from randomly gathering water and producing H2 and O2 with the same energy source?
Hydrogen is actually kind of scarce in the inner solar system, so metal ion thrusters would be be useful for low-thrust applications.
TIL Falcon 9 uses plasma thrusters. (I’m reasonably confident it does not.)
Did the author mean the hall-effect thrusters used on Starlink?