The flat world generation presets have not been updated for the new world depth in 1.18 – for example, the "overworld" preset in 1.16 contains 64 layers, putting the ground level at y=64, same as the typical worldgen ground level.
In 1.18 and 1.19, this preset has not been changed, resulting in the ground level being y=0 instead.
Oddly, the "ocean world" has had 64 layers of deepslate added to it, so it behaves like in 1.16. But the others have not.
Comments 3
Weird that didn't come up when I searched for it. However, at least one of the bugs in that chain needs to be left open – it looks like they've all been mutually closed as duplicates, which means nobody will ever get around to actually fixing it.
Not a bug. It is considered a feature request for Feedback and Suggestions per @unknown.
"Feature Request"
Thank you for your report!
We're tracking this issue in MC-215423, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as invalid. Please take a look at the parent ticket (MC-215423) and see if an explanation is provided there in the description of the ticket or in the comments for why this issue is invalid.
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