Ethernet was always better than Token Ring
I worked at 3Com for a while. I did both Ethernet and Token Ring designs.
Ethernet blew Token Ring out of the water, on design simplicity, speed, reliability and cost. Token Ring was a nightmare to keep working. It may have worked fine at 4 megabits, using the special IBM cable, but when they tried to push it to 16 megabits over category 3 twisted pair, the technology wouldn't scale. It was an EMI nightmare, required proprietary MAC microcode on each node and never dropped below a 3-to-1 cost premium, compared to 10/100 megabit Ethernet interfaces.
There's a reason it's not around anymore. Token Ring had a narrow niche market, places where IBM convinced customers that reliability and determinism were worth paying for in performance and cost. That advantage disappeared with the advent of cheap 10/100 Ethernet switches, something else that 3Com was good at building.
3Com had its problems, but Ethernet was not one of them. For a long while, 3Com NIC cards were the premium quality choice. That advantage only faded when Intel got into the market.