No, because thrust per unit power drops as exhaust velocity increases. You’ll be increasing your power supply and thruster mass far more than any propellant you save. It’s also energy inefficient to use too high of an exhaust velocity.

The mass-optimal exhaust velocity is approximately equal to the square root of (twice the thrusting time times overall power-and-propulsion system specific power times electrical efficiency).

Read more here: https://ocw.mit.edu/courses/aeronautics-and-astronautics/16-...

Assuming no dry mass (spherical cow!), energy optimal Exhaust velocity is equal to the total elapsed mission velocity at any point. If you can’t adjust exhaust velocity, it’s proportional to approximately to 60-65% of the total mission delta-v (off the top of my head). More discussion of where this energy-optimal exhaust velocity comes from: https://www.youtube.com/watch?v=ogKKjpQvfuM