My first job out of school in 1998 was writing test plans for the antenna pointing and tracking for the Teledesic CPE at Motorola. If I remember right, the initial plan was to have dual steerable dishes inside a pair of radomes—like a pair of Mickey Mouse ears. There was a vague future plan for phased-array antennas, but at the time it wasn't realistic to talk about getting them on roofs at a reasonable price point.
The bigger challenge was the optical intersatellite links; routing traffic between LEO satellites using lasers. The lasers had to track satellites in adjacent planes of the constellation that were traveling in the opposite direction.
It's interesting to see the same general idea for the large constellation come up every few years. If we had actually started building it in 1998, it would've been on a second or maybe even third generation by now.
I'm a little surprised that Apple hasn't given it a try with their billions sitting around. 4K FaceTime, or even just downloading movies or apps instantly would be a selling point for their other hardware.
Didn't Iridium get around that by having a single "seam" between adjacent oncoming planes which signals don't pass, but for all other adjacencies using crosslinks between planes?