If they were the same cost I'd pick the train every time. I can relax, sleep, read a book or get some work done.

I really wanted to take a train or greyhound, wasn't super picky, for my last two trips but it was stupid. I had naively assumed the tradeoff was going to be adding about two days to the trip for travel there and back but in exchange it would be a lot cheaper than a flight. Nope. I guess. For some reason. Same travel days, same destinations. Not only were flights, obviously, faster but they were cheaper too.

Pay more for fewer departure/arrival options and turn a few hour hours into +1 day on each end seemed not worth the vibe.

Yeah if you live in the US then the trains and buses aren't really an option I guess.

It's substantially safer as well.

> So the only thing it offers is being cheaper than renting a car for one extra day for long journeys

Nope. It also offers not having to drive. I can read a book on a train, which I can't do in a small car even if I don't drive because I'll get car sick. I can even walk around and have luch in the train restaurant, go to the bathroom without having to stop.

Going by train still has the benefit of being able to do something while you travel. Especially relevant for solo business trips.