Surely you must mean 80 MEGAbits per second, not 80 KILObits per second, which is a factor of 1000 times different…
And you also seam to be comparing FULL duplex to HALF duplex, which is not correct.
The WDTV is FULL DUPLEX, and I’m assuming you have a somewhat modern network switch, which means you have 100 megabits per second in EACH direction, not total, likewise with Gigabit ethernet, you have 1000 megabits per second in each direction. VERY FEW (if any?) devices do Half-Duplex gigabit.
When copying or streaming files, you should NOT normally be seeing the exact same number of packets going out as in, unless you’re doing something weird like copying a file FROM the WDTV’s storage TO another place on the WDTV’s storage, in which case they’d be close to the same in quantity.
If you’re copying a file from the WDTV to your PC, you should see roughly 2x to 10x the number of packets OUT as IN, depending on how the transfer protocols negotiate the connection (the TCP segment size is the biggest contributor to this difference.)
But to answer the root of your question, the Hub struggles to do much more than 100 megabits per second, but it can do slightly more under good conditions (120 megabits per second or so on Gigabit) and 80 to 90 megabits per second (depends on how you measure) is pretty good for 100BaseT network.
Does this help?