Outdating a world regenerates it from 0

When a world generated from 1.13 or more is outdated, the world instead of eliminating the related changes, in these more current versions, regenerates the world of 0 eliminated all changes made by the player.

This bug affects the versions:
1.13 and / or +
1.14 and / or +
1.15 and / or +
20w06a and / or +