A little bit of both, and they are related. Trains are a tough sell because they aren't competitive for most travel. Even at 300kph, they're only good for local-ish travel (by that, I mean up to perhaps as much as 1000km). Would be great for Portland to Seattle, or Portland to LA, but if you're going out of region (which is extremely common), an airplane will be way faster and almost certainly cheaper too.

I'd love a moderately fast train, say 200kph, between cities like Portland and Seattle. That's a great use case.

But as a nationwide network, there won't ever be a suitable rail alternative, unless it gets subsidized. Amtrak is already stupidly expensive for what you get.