Probably not, as modems connected to Macs via a round serial port identified by a phone icon and Ethernet ports were originally AAUI (D-shaped transciever port

Probably not, as modems connected to Macs via a round serial port identified by a phone icon and Ethernet ports were originally AAUI (D-shaped transciever port similar to AUI but with a smaller connector) or, on some of the old NuBus cards, 10BASE2 (coaxial). I suspect it's just a stylized double-ended arrow representing bidirectional data transfer, created because Apple (or whoever) needed a localization-agnostic way to represent "Ethernet" on hardware.