Industrial control rooms were built from square tiles that clipped into a grid — 24 mm each, four legs, snap in, snap out. Each tile could be a painted line, a lamp, a counter, or a switch. Click the cells. The thing to notice is that the display resolution and the input resolution are the same number, because they are the same square.
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The pitch is set by the finger, not the eye. At a 2 m viewing distance a 24 mm tile subtends about 41 arcminutes — roughly 41 × the one-arcminute limit of human acuity. As a display that is absurdly coarse; you could read something forty times smaller. But many of those tiles are switches you have to hit with a fingertip, and the pitches on offer — 18, 24 and 48 mm — sit right around the 19.05 mm pitch of a standard keyboard key. The grid was dimensioned for the hand.
Which is why the comparison with a screen is lopsided in both directions. A 2 × 1 m panel at 24 mm holds about 3,400 cells — a little under twice the 1,920 character cells of a VT100 terminal, and about 1/600th of the pixel count of a 1080p display. The screen wins the display contest by nearly three orders of magnitude and loses the other one completely: you cannot press a pixel. On the panel every cell was addressable by a screwdriver and, where it mattered, by a thumb.
Assumptions. Tile pitches of 18/24/48 mm and the 96 × 96 mm carrier grid come from current suppliers' catalogues — these systems are still sold. Note that 96 divides evenly by 24 and 48 and not by 18, so the 96 mm carrier belongs to the 24/48 family; so the 18 mm system must use a different grid — which one, I have not established. Acuity is taken as one arcminute, which is a normal-vision convention rather than a hard limit. Cell counts are the naïve floor of panel size over pitch and ignore frame borders, so a real panel holds slightly fewer. The VT100 figure is its 80 × 24 text grid, not its scanlines.