Some distance can cause the piston arm to disappear/not load properly, and this is most obviously affected by the simulated distance, especially when the simulated distance is 4.
For example, if I look at the piston in (-15, -32), you will find a piston without a piston arm,
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Piston arms are tile entities and have the same render render distance as other tile entities such as chests. This is a Level of Detail optimization. Tile entities use much more processing power to render: see MCPE-157252.