The start height value is unable to be altered on monuments (and probably desert pyramids too).
By default, the terrain adaption is set to none, but none of the options, even when enabled, affect the height of the monument.
The monument seems to be hardcoded to always be 2 blocks below the surface.
Linked issues
Comments 1
aceplante
Thank you for your report!
We're tracking this issue in MC-226687, so this ticket is being resolved and linked as a duplicate.
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