People are getting the whole history of ECPA totally mixed up.
ECPA passed in 1986 because CTIA wanted it. Then they could claim that cellphones were "private" without having to invest in the technology that would have prevented interception. Industry reps promised Congress that encryption would eventually become standard, which never happened. Other industry groups wanted in, too, so for convenience Congress also threw in prohibitions against intercepting STA frequencies, commercial paging, and direct satellite downlinks, as well as anything encrypted.
In 1994, TDDRA amended ECPA by adding cordless phones to the prohibited monitoring list. This happened because of an intercepted cordless phone call in Florida that was probably hunted down and then publicized for partisan reasons (the people who claimed the "accidental" interception on their kid's police scanner - the Martins - were members of the local Democrat Party organization and Gingrich wanted to run for President as a Republican). The scandal went nuclear when politicians realized, not that an ethical problem might be discovered, which they had procedural ways of burying, but that their "private" affairs of other kinds might be revealed.