Actually, that's not entirely true. Compared to 1971, there are more corridor services with more frequent trains and faster schedules. This is especially true for the NEC where the 65-70 mph point to point average speed of the Northeast Regional Actually makes taking the train between New York and Washington faster than driving. However, there are numerous other places across the country where there's relatively frequent short haul passenger rail service as a transportation alternative.
They have also increased long distance trains, at least compared to May 1, 1971, even though some of the added trains later bit the dust. They also did modernize the equipment. Sure, that was 40 years ago, and now it's time to modernize it again, but they did replace the Heritage fleet.
And even the current mess with degraded food service has its precedent, and there's hope that improved quality food may return. I once rode the Crescent in 1990 and had obviously microwaved fish (no Airplane! jokes, please!) served to me on Styrofoam plates with plastic cutlery. By the end of that decade, they had reverted to serving real food in the dining cars.
In 1971, it looked like intercity passenger rail travel was about to go the way of the horse and buggy. That hasn't happened, thanks to Amtrak, for all its shortcomings.