I was lucky to take my bike up to Cumberland, MD from Raleigh, NC a couple of years ago by train to do the C&O trail. I really do wish they’d offer more ways to travel with your bike, because that was a great experience. I’ve also done the trip from Raleigh to Durham, which makes for a nice little day trip.

What's the issue with it. When I take the train to Portland from seattle they just roll the bike on and I grab it quite fast when I get off. Sure it's in the bag car but it's a 3-5 hour ride

Every time ive tried to book a trip w/ bikes for me and friends they never had enough availability. It was always limited to 3 bike spots

ok, yeah that sucks. Esp on a commuter train. The portland route will generally just toss extra bikes on in the baggage car and strap them up. yes it can damage your fancy ass paint job.