You all have forgotten a very important point why a sleeper train between Montreal and New York City is not going to happen! The towns and cities in between are not going to attract as many passengers in the middle of the night as they would during the middle of the day.
Just look at recent ridership data for the Adirondack.
https://www.railpassengers.org/site/...es/3454/40.pdf
Albany-Rensselaer 4,802
Croton-Harmon 2,855
Fort Edward 4,450
Hudson 1,436
Montreal 73,872
New York 97,350
Plattsburgh 13,325
Port Henry 2,395
Port Kent 521
Poughkeepsie 3,012
Rhinecliff 900
Rouses Point 1,276
St. Lambert 1,086
Saratoga Springs 17,398
Schenectady 8,518
Ticonderoga 2,246
Westport 5,626
Whitehall 1,776
Yonkers 2,476
Top city pairs by ridership, 2017
1. Montreal, QC - New York, NY
2. New York, NY - Saratoga Springs, NY
3. New York, NY - Plattsburgh, NY
4. Albany-Rensselaer, NY - Montreal, QC
5. New York, NY - Westport, NY
6. New York, NY - Schenectady, NY
The data listed above is specifically for the Adirondack trains and not other Empire Service trains.
While Montreal to New York is the top city pair, other city pairs with New York are higher than the next city pair with Montreal. Any night sleeper train will probably scare passengers away from the intermediate cities and get significantly lower low ridership in the middle of the night.
I do not think the politicians from New York State, especially from Upper New York, will be as willing to subsidize higher loses for a poorly time train. And make no mistake, New York State is subsidizing this train, no one from Canada is.