Parity issue: /spawnpoint does not seem to work in custom dimensions

The Bug:
/spawnpoint does not seem to work in custom dimensions unlike Java, even though in Bedrock /spawnpoint works in the Overworld, Nether and The End dimensions. Bedrock Edition has custom dimensions now under beta APIs.

Steps to Reproduce:

1. Download and install the example behaviour pack.

2. Create a new world with the Beta APIs experiment enabled and have the custom dimension example behaviour pack enabled.

3. Use the /dimensions command added by the pack.

4. Select the Sky Lounge custom example dimension.

5. Once in the custom dimension, run /spawnpoint

Expected result:

/spawnpoint will work in every dimension, even the new custom dimensions from the newly released custom dimension API.

Observed result:

/spawnpoint doesn’t work in custom dimensions.