IMHO, ADM1 & ADM2 were children of their time ...
AFAIK, ADM1 was introduced with Progress V8 (1993?), Progress' first stable release (IMHO forget Progress V7) to support a Windows GUI client. At that time client/server was state of the art and the world of coding looked completely different back then.
ADM2 was introduced with Progress V9 (1998?), utilizing the then new 4GL language features like dynamic objects (mainly queries and buffers), publish & subscribe and super procedures. This allowed for a much better framework which somehow mimicked OO behavior - but this was way to progressive for most Progress developers out there. At that time n-tier architectures were widely accepted as the right choice for flexible and scalable applications - but this was way to progressive for most Progress developers too. But, IMHO, the Progress GUI (Windows95 look 'n' feel) did only allow for retro GUIs and most Progress developers felt not very comfortable to use OXCs to pimp their UIs.
In retrospect Progress failed to spread their state-of-the-art technology into their customer base and most of this customers were mostly concerned about UI functionality than they were about application architecture. And that was the weakness of Progress: Compared what competitors offered on the UI front Progress was more than just one step behind. In the end these frame works never got adopted by a broad enough customer base and although they showed great potential, Progress let them die a slow death ...
But, when you compare ADM1 and ADM2 with recent state-of-the-art technology, of course they suck, but so would everything else if you would compare what M$ and other competitors had to offer back then (10 to 15 years ago).
Regards, RealHeavyDude.