There were even companies that made a living selling kits to retrofit these tubes into computers that came with the "bad for your eyes" white phosphor tubes. Somewhat ironically, given the increasing focus on ergonomic issues in the latter half of the 1980's, monochrome monitors ended up moving almost entirely back to the white phosphor in large part because of how the Macintosh pushed the "screen as a literal representation of a piece of paper" metaphor into people's heads; paper is white so the screen should be white, right!
Anyway, after the death of mono monitors the word "ergonomic" was used throughout the 1990s to describe color monitors that supported higher-than-60hz refresh rates designed to reduce detectable flicker so, yeah, the word totally applies to "measures to reduce eyestrain".
(You won't see it very often *directly* applied in, say, archived sales material for green monitors, but that's mostly because the word "ergonomics" wasn't really in vogue until the mid-80s. But there are examples to be found.)