Structure 'End City' and configured structure in vanilla end 'End City' use inconsistent identifiers
The (not - configured) structure has id "minecraft:endcity" and the struture in the end lists as "minecraft:end_city".
It is now imprtant as worldgen is now publicly accessible via datapacks, not an internal concept
Since all identifiers use snake case consistently, suggesting encoding structure name as 'end_city', the same way you have fixed all instance of 'village_snovy'
Attached screenshots of vanilla world gen json for end_city structure
There are another related issues that point to different identifiers related with end cities:
MC-187911
2020-07-21, 08:25 PM
2022-05-27, 08:42 AM
2022-05-27, 08:42 AM
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