Yes, counter mode wasn’t novel at the time. The actual idea was related to encryption of network traffic. Back then, networks ran faster than encryption (processors didn’t have encryption hardware support). Since many networks have bursts of transmission the idea was to encrypt a counter with buffering of the results. This buffered stream of crypto values would then be XOR’d with the data when it arrived. The xor of course can run at full network speed since the encryption was done while during an idle time of the network.

The method takes advantage of network idle time so it doesn’t improve maximum bandwidth but instead reduces the average latency of a network not running at full bandwidth.