In article ,
I think you forget about the CarterPhone decision.
Final decision, merely six years before the filing of the lawsuit that led to the Bell system divestiture.
Bell system (nor any other telco) could not require use of "their" interface equipment. So the 'third party' market for 'attachments and peripherals' would have bloomed -- as it, in fact, did -- regardless.
The primary "alternative" long-distance carriers (United Telecom and MCI) were already building out their own long-haul _physical_plant_ infrastructure long before the Bell system break-up occurred. Well before the the lawsuit was even filed.
As "_off_ ARPAnet/NSFnet" IP use spread, going to the 'alternative' carriers for point-to-point _data_ connectivity was a "natural". both ends were going to be in 'bigger towns' -- the places the alternative carriers serviced _first_; it was *not* covered at all by PSTN regulations, none of the regulatory/tax issues of 'by-pass' came into play, etc. And those alternative carriers could offer better quality circuits, *cheaper*.
And, of course, MFS had been doing the same under-cutting in the city-center for high-cap 'local loop'.
If the "Bell System/AT&T/Western Electric" had remained a monolithic entity, The rate of change in the "Internet" would likely have been much slower. There probably would not have been the telecom boom/bust of circa 5 years ago,
OTOH, DSL would not likely be ubiquitous, as it is today; "high speed" to the residence would probably mean 2-B ISDN.; today's "date" would probably be "September five-thousand-and-something" instead of the current number.
[TELECOM Digest Editor's Note: Sounds a little grim to me. PAT]