Except I'd contend, at a bare minimum, that there are at least two buckets of rich and two buckets of poor. On the high end you have the (relatively) super-wealthy who are willing to do cruise trains and the like. This is the Prestige Class crowd (or International First, in a sense).
I think very few of them are riding trains. Only a few are railfans -- not enough to make a significant, every day of the year, market -- and those are happy with the same service as the next category. They might take private cars if they had the option, but private cars don't operate often enough or to enough places.
Then you have the more moderately wealthy (this brings in the upper end of the middle class such as it is). These folks can work with the current fares/offerings, though you might have some room to bring in more volume with a modestly improved product (e.g. better mattresses, modest improvements to food service) at the current price point. This is, by the way, going to include a subset of folks traveling for non-experiential reasons. Call this International Business.
I'd describe this market as people like me who have enough money to travel however they want, but really strongly prefer to ride trains. The
vast majority are travelling for non-experiential reasons -- we just don't like flying / driving. And we have money so we would like to take the most comfortable way we can afford.
And how much we can afford varies, by person and by year. There's room for a lot of differentiation within here, because this is the exact market where hotels offer an endless series of small upgrades. (Queen? King? Two Queens? Balcony? Slightly larger room? Would you like breakfast included? Chocolate on your bed?) In "cruise trains", this is where the Grand Canyon train can offer a ridiculous number of different classes of service, each slightly pricier than the last.
On the "poor" end, you've got a group that's going to chase the cheapest fare in a condition they can tolerate and that's gonna be whatever seat is available. This is a subset that will travel from New York to Miami in a Regional coach if it will save them $20.
Amtrak is losing these people to sketchy bus operators with unsafe drivers and unsafe buses, or if those aren't present, Greyhound or Trailways. And frankly I don't think Amtrak can compete on price with those bus companies. And it shouldn't. In North Dakota, you'll get these people because there aren't any buses, though.
Then you've got a group that is looking to save money, but for a variety of reasons will fork over for the equivalent to "premium economy" in this context.
I think this is Amtrak's core coach-class market. People who don't want to spend much money, but, just like the wealthier equivalent,
don't like flying or driving or taking the bus.
To be fair, that last group may also include some shorter-haul pax who don't want "just" a coach seat but can't justify a roomette.
Which probably justifies a "business class seat" offering. I'm old-fashioned; I like the idea of "first class, second class, third class, fourth class, fifth class", but for marketing reasons every company has avoided those names since the 19th century.
VIA handles the first three groups reasonably well (with the first two consolidating down in the Corridor due to volume vis-a-vis Amtrak).
I think the first two aren't very distinguishable, frankly. The true super-wealthy are in private jets, typically.
Amtrak handles the second and third well on the LD trains, and also sweeps in the first group on the Acela but ignores them elsewhere. Neither Amtrak nor VIA really hit on that last group or differentiate the last two from one another terribly well, particularly in the LD market.
Fair argument. But see my view above.
Coach should be a "premium economy" service at all times, with business class being available everywhere; Amtrak's doing sort of OK at this except for wild inconsistency of both hard and soft product. They can sell leftover seats to the "cheapest seat" people if they haven't been sold and it's near departure, but the "cheapest seat" people will still mostly take the bus.
On what you'd call "international buisness" -- the "we've got money to spend" category -- Amtrak's doing pretty poorly right now, mostly due to extremely weak soft product, but also due to poor maintenance of the sleeper cars and of course terrible OTP. There's also not enough differentiation available here; this is a category with infinite differentiation at hotels, and while Amtrak can't generate that much differentiation, it should be able to do more.