Using the /place structure stronghold, it spawns a stronghold without corridors. If you try to spawn the stronghold on y = -64 or higher it will spawn on y = 0 and higher.
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This is because stronghold generation is made to replace non-air blocks with the room/corridor walls, floors and ceilings. You're placing it in a location with no non-air blocks to replace.
I'd argue the resolution here is wrong, and should read "Works as Intended" instead, as it does exactly how it is supposed to generate.
Relates to MC-251339, which is also an issue with structures not carving out any air spaces when placed.