Having had extensive experience with Nextel (being a former
employee in Corporate Sales and also a iDEN fanatic during the "glory days"
of Nextel) something things folks need to realize about Nextel:
Nextel was initially conceived of as a two way radio service
with phone service as an afterthought. When it first debuted
as FleetCall under O'Brien/McAuley data/mobile web was non-existent
and even basic text messaging was in its infancy.
The Iden network that Nextel had was NEVER designed to handle the amount of heavy data traffic that is in use today. It was designed for Walkie Talkie (Direct Connect) primarily and phone secondarily. It did both of those well but data was always an afterthought.
I remember as an employee tethering my EBP (Employee Business Phone) to my laptop in 2004 using Nextel's
Packetstream Gold service at the "blazing" speed of 19200 baud
That was freakin painful!
Heck, I used to do a decent side business of loading personal ringtones/wallpapers on folks Nextel phones back in the day because the phones themselves would not let you do that (Webjal anyone?

)
Besides the limited data capability the other thing that doomed Nextel was opening up the service to the pre-paid market through Boost Mobile. Once Boost Mobile came around and became popular the Iden infrastructure could not handle the amount of users on the network and became "bogged down" and overloaded. Service quickly deteriorated and the post-paid (contract) user base became very unhappy.
Add in the fact that Sprint did not have a clear plan of what to do with Nextel or how to integrate it with their disparate CDMA network from the beginning. I can say with firsthand knowledge they had no official "roadmap" or plan of what they wanted to do with Nextel longterm. By the time that Sprint came out with the hybrid CDMA Phone/Iden PTT phones it was too late.
Iden was doomed due to its own data limitations plus its positive Walkie Talkie features being squandered by Sprint.
I still say if it could have been kept online as a PTT (Direct Connect) Walkie Talkie service
ONLY it could still be a great (Mostly) Nationwide service today (yes SouthernLinc is in there too).
I will always look back on my days of "hacking" Condor/Falcon Nextel phones using RSS to enable features fondly. It provided me great insight into how iDEN (and radio systems in general) operate.
RIP Nextel and thanks for the fun times!
I will always keep my heavily customized I90c/i95cl/i730 as museum pieces

Marshall KE4ZNR