Yep. It is just bullshit greenwashing. Green rail is solved. It is just running on the grid, and trying to turn the grid as green as possible. All this other stuff is bullshit.
From a technological point, yes. That being said, there are some complications. The US runs double-stacked intermodal freight so clearance is a concern, first of all. It's doable, in fact India has many electrified lines that allow for double-stacked intermodal freight, but it does add a little to the cost and effort. The second issue is, unfortunately, cost, but not because it's outright "too expensive". Rather, it would eat too much into the short-term quarterlies of the various publicly traded rail companies that own a vast majority of the US's rail lines during the installation. And as publicly traded companies, even if one of the major rail companies wanted to spend the money to electrify, they would get sued by their shareholders for doing so because there's no immediate return on profits. And the final issue? NIMBYs already hate rail as-is, they'd hate the overhead lines even more.
So, yeah, a lot of challenges to electrification unique to the US, almost all of them political in nature. It would be really nice to put in electrified rail again (late PRR and New Haven were almost fully electrified but most of that was ripped out after the Penn Central merger. Seriously, everyone likes to rag on New Haven for screwing that up but honestly the evidence all points to the New York Central's management team being the real culprits).
It's kind of sad that we live in a world where even if a CEO wanted to do something to help the planet at the expense of his own profits, they'd be sued for doing so.
As a tribute to its efficiency, the train has also been entered into the Guinness World Records database "for the longest distance of 1,741.7 miles achieved by a pilot hydrogen fuel cell electric multiple unit passenger train without refueling or recharging," according to Stadler, the Switzerland-based manufacturer.
Guinness world records are almost universally bullshit, and go to whoever has the money to pay for someone to come out and verify that they can actually do something, but good grief that's a lot of qualifiers.