Lots of forms of art don't get a genera name until after they've started ;). Just because the first "cubist" painting came before the term got coined doesn't mean it isn't a cubist painting. And just because this showed up a few decades before ASCII itself was hammered out doesn't mean we all don't know exactly what it is when it's described as ASCII art.
For that matter, it's not "ASCII art" because it's encoded that way (as opposed to "UTF-16 art"), it's because it's made up of text characters in a grid.
This certainly counts.
It is also reminiscent of an embroidering pattern.
I agree - I think this is more a cross-stitch pattern than ascii art - especially since it only uses one character (X). It is however quite fancy, and I do appreciate the time it would have taken to produce it.
I imagine you could just trace over an existing picture then type X's over the tracing paper, with a typewriter.
You still need a monochrome [0] picture that looks good at low resolution.
[0] Or rather bichrome.
Was Jesus Christian, and were Neandertahls from Neandertahl, and so and so...