Judging from when I rode in 48/49 sleepers (getting ALL meals in the cafe since boxed dog food) and 448/449 BC and coach in the past couple of years, it's been hit or miss on occupancy rate in business class. The ONLY time I saw 15 or 16 of the 18 seats occupied was during holiday periods. Other times, it was usually less than 1/2 full. On 49 leaving Toledo a few months ago, I think I counted 3 passengers when I went to the cafe.
So I'm guessing it's a lack of patronage that has driven the decision to drop the BC section. But...at the same time, I suspect Amtrak is considering the food-less coach passengers on 48/49 between NYP and ALB. If I were to make a wild guess, it would be that a full cafe car will be added to the NYP section and cutoff at ALB to be replaced by the BOS section full cafe car when the trains are put together, given current switching routine at ALB - NY section dual mode locos cut off, entire BOS section, locos and all, added at front of train. Process reversed eastbound. Having the NYP cafe car removed with the locos at ALB makes sense and solves the 'no food' problem. However, how many NY section passengers will 'like' being tossed from the cafe at ALB?
And, for what it's worth, thinking that perhaps they simply switched the BC/cafe car to the NYP section I checked BC availability ALB-CHI. NOPE. THAT would make sense to run the BC/cafe car NYP-CHI and remove the cafe from BOS at ALB.
In the end, ditching the BC section and making the car a full cafe will allow the crew to take 2-3 full booths for their 'stuff' and nobody will scream. Or, maybe they'll take out a couple booths from the full cafe cars and put in bike racks. Again, nobody will scream as there would still be 10 booths wide open, minus 2 or 3 for the crew.
Oh, and by the way...legroom in an Amfleet II LD coach is 22" from front of seat cushion to rear of fully upright seat ahead. In combo BC/Cafe cars, the legroom is only 18". Yes, I personally measured them! Other than the free beverages and an improved sense of 'privacy' in BC, I consider the Amfleet II coach seating more comfortable and 'open' when I can get the whole seat to myself.