network "congestion" my ass. look how quick they are to offer more when they look comparatively bad
The pricing of bulk data plans is nearly independent of the congestion issue.
If (as Verizon claims) congestion mainly effects a small percentage of cell sites at peak times of the day, they can offer bigger data plans without incurring much additional cost. They don't have to add any new infrastructure to do this; most of the network already has excess capacity most of the time.
Most customers who get the new larger data plans either won't use the extra data, or will use it at off-peak sites and times. The relatively small number who mostly use peak sites and times may still be throttled at those sites and times.
Verizon clearly thinks the cost of NOT offering better data plans would be too high (in customers lost to the other carriers).