Back in the early 1990s, mice were fragile enough that Apollo salespeople were trained to be able to do their demos keyboard-only as backup (at least for trades

Back in the early 1990s, mice were fragile enough that Apollo salespeople were trained to be able to do their demos keyboard-only as backup (at least for tradeshows) and that was just generally how interfaces were built. It wasn't an accessibility thing, it was a "we're demoing expensive systems to even more expensive people, it had better work" thing...