The DXA semantic mapping logic tries to "de-pluralize" List-type property names. For example, if a List-type View Model property is called "Articles" (plural), it implicitly maps to a CM field called "article" (singular).
The rationale behind this de-pluralization is that it is a common practice in CM to give multi-value fields a singular name; the field name is used as the XML element name and XML elements are used for each field value.
However, it has become clear by now that this de-pluralization logic is not obvious and causes a lot of confusion for people. Furthermore, the implementation is oversimplified (it simply removes the trailing "s" if any) and hence only works properly for some english names. For example, a List-type property called "Buses" will implicitly map to a CM field called "buse" (rather than "bus").
So: it seems the "smartness" in the implicit mapping is doing more harm than good; I think it makes sense to report this as an issue on GitHub.
However, there is an easy work-around for this issue: don't rely on the implicit mapping, but use explicit semantic mapping. For example: