In an earlier post I pointed out the following:

Many on this subreddit (and elsewhere) mistakenly believe that "most myths and legends are either based off some semblance of truth or attempt to convey some message..." The belief that this is true can be regarded as a bit of modern folklore. Like many beliefs, it is often accepted as widely accepted and completely valid, but there is not evidence that at least the latter is true.

Folklorists Alan Dundes and Jan Brundvand independently attempted to "chase down" the original incident that inspired various modern "urban legends." They consistently failed. Where these stories came from is extremely difficult to fathom, even though most clearly are modern and one would think with all the tools available in a modern age, that it would be possible to track down to their point of origin - whether as a real incident or as a fabrication. Given those failed modern attempts, it is even more problematic to track down what an older story was "based on." In other words, we really need to accept, simply, that it was a good story that people told and retold, and where it came from is not likely to be known with any certainty.

That doesn't prevent people from attempting to find the "real" thing that was behind an older story. These efforts are always speculative. Some speculation is better than others and can be reasonably persuasive, but we cannot lose sight of the fact that in attempting to connect the dots between "this story" and this or that historic event/character is filled with speculation. It is a fun parlor game, but it is not anything that can be objectively accepted as fact. Good stories are, simply, just that, and we are all subject to a good story - and we like to repeat them.

That’s the context that causes me to be extremely skeptical about anyone who claims to know what is behind a given motif. The assertion that the motif in the folktale “Hansel and Gretel” provides a direct link to an earlier famine is pure speculation, it is unlikely, and it cannot be proven.

The folktale that appears in the Grimm collection is part of a large complex of folktales and their variants, which folklorists describe as “ATU” Tale Type 327. With the wide distribution and variation of these narratives, it appears that this tale type is old – and likely to predate the 14th century.

Uther, Hans-Jörg, The Types of International Folktales (Parts I–III) (Helsinki: FF Communications No. 284, 285, and 286, 2011).