Umatic was originally conceived as a home or consumer format, but its size and cost for tapes and gear were a bit out of reach for most consumers.
When Porta Pack "portable" machines and relatively small cameras became available, Umatic was very widely adopted for Electronic News Gathering (ENG), to replace 16mm for this purpose, and remained in use for many years, so as such it did make "network" air.
Long after other formats came into use, 3/4" Umatic remained as an exchange medium for review, since pretty much every ad agency and tv station had a machine somewhere around. Also for many years, and maybe still true in some areas, cable TV providers used 3/4" for local origination playout.
It's The Format That Won't Die.
Umatic came out more or less at the same time as "Sgt. Pepper", I understand. I spent the 80's lugging that stuff around for news and documentary production, gave my spine a permanent curve. We still get the occasional request for dubs in that format, but very infrequent finally. Still in the multui-year process of burning all our old 3/4 and betaSP to DVD.
When they came out, the early top-loader models came with first an outboard, then built-in TV tuners for VHF and UHF reception, and a primitive, analog-based alarm-clock-like timer mechanism for recording and time-shifting programs. But as was said, these were generally owned only by the very rich and a very few advanced "early adopters", people in show business and such.
Umatic started taking off as a news and training format when the portable decks came out and a compatible "mini-size" tape cassette shell (20 minute loads, woot!) shrunk the size of the tapes from about New York phone book size to Gideon Bible size.
I spent over 10 years dealing with 3/4" U-matics. Sony developed the format to be a "prosumer" product, but, almost at the same time came out with the BVU broadcast line, which had many more built in and optional features such as a TBC and SMPTE timecode. Many small TV stations used BVU VCR's to broadcast nearly everything and even the networks used their BVU u-matics to broadcast news, and in some cases, it was broadcast right from the edit bay because of time constraints. Near the end of its life, the U-matic SP line appeared with (slightly better quality), which could be compared with the difference between plain VHS and VHS-HQ.
Because I was afraid of getting caught with hundreds of tapes and no way to play or transfer them, I first bought a set of 2860 editors to keep new in the box and then a pair of 5850 editors, which I just recently took out of the cartons to do a job with. What looked great at the time, is VERY disappointing by todays standards. Today, tape is virtually obsolete.