Why does OpenStreetMap Boundaries have different data than OpenStreetMap?

Question

OpenStreetMap

(This is NOT about politics, but about the technical part.)
Crimea in OpenStreetMap seems to be in the Russian Federation: https://www.openstreetmap.org/relation/3795586, name="Republic of Crimea", addr:country="RU", ISO3166 -2="RU-CR", "Relationship Southern Federal District (1059500) (as subarea)".
(There is, however, another Crimea, https://www.openstreetmap.org/relation/72639, but this is not about him.)
So, downloading the Russian Federation in OSM Boundaries , I don’t see a single Crimea there, but two Sevastopol .
And in the search for https://www.openstreetmap.org/ itself , it is displayed like this: "Results from OpenStreetMap Nominatim - Region / State of the Republic of Crimea, Ukraine".
How does it all work? Why (technically, where can you see this?) do these sources have different affiliations? In each of the two, except OpenStreetMap itself, cases?
See also my post: https://forum.openstreetmap.org/viewtopic.php?pid=...
Thanks.

Answer 1

Well, this is so that you can choose the one that you like best.
In general, there are two sets of data, where only the parents are different.

Answer 2

an error in the algorithms for processing osm data on the osm boundaries site is not
excluded