My recollection is that the dots were round on my dot matrix. But it also used a typewriter ribbon, so there was a bit of texture from that.

Good point, the dots were produced by pins that were round. What I meant to say was that the spacing might have been different in the two directions.

Yes, I’m sure they would be. Especially since the same font would have been used for normal width (10 characters per inch) and compressed (17 cpi).