96 bytes was a lot of data in the mid-80s. On a 1200 bps connection, that's almost an entire second per packet. When I was a college student in the early 90s, we had 2400 bps modems in the dialup pool, and the entire university (~3000 students) lived on a 56k leased line. Nowadays, that's trivial. In 1984, not so much.
OTOH we didn't run SLIP (PPP wasn't invented yet) over our 1200BPS/2400BPS modems, at least I don't know of anyone who did, except as a test. We ran terminal software to login to the university computers remotely. So address space wouldn't have impacted that much. In fact, where I was, TCP/IP didn't become a thing until we were connected to the internet proper. (1988), but of course YMMV.
That said, 16 bytes for an address would probably not have flown. But 6 I can sort of see.