I believe freight typically has RoW priority over passenger fleets That's a big part of it. The other part is that UP is making electrification difficult and

I believe freight typically has RoW priority over passenger fleets That's a big part of it. The other part is that UP is making electrification difficult and more expensive. UP wants to run double stack cars but the overhead wire would eat into the vertical clearance. I believe there were issues raised with horizontal clearance too.