Yes, at least, when I read the term in a post referring to Wiki documentation and that would then be the German one. I understand from the article: Shared use is a technical term exactly for ways explicitly and officially signed. Others are unspecific use.
The German map style renders paths and foot/cycleways differently. From panning around a bit in my area, ways as in your picture mostly mapped footway not path. The bottom one likely as a track. Actually, we do not have many such ways even though a highly touristic place. Walking and cycling routes reuse agricultural and forestry infrastructure a lot.
A specification for a “mup” (multi-use-path) that will include weaker forms of designation in your pictures certainly will make more sense than strictly mapping signs. But classification will get trickier.