The problem with the dismount idea is caltrops existed already. Way easier to make. Sharp and therefore much more effective.
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We have antitank missiles, but antitank mines already exist and are way easier to make.
But that’s an apples and oranges comparison. Missiles are active, mines are passive. One you aim. One you leave somewhere inconvenient to the enemy. Basically mines are the latest most advanced version of caltrops. These dodecahedrons would just be a harder to make less effective version of caltrops. It would be a backwards step.