« earned its own spot »
Linguistically, this chart doesn't have much value. Not sure what criteria were used for inclusion of this or that item, perhaps just presence in some ISO standard. “German” per se doesn't mean much, so-called “high-German” („hochdeutsch“, meaning „oberdeutsch“ in opposition to „niederdeutsch“), the language that you and I speak, is an artificial synthesis and administrative compromise on written variations that is not organically rooted in dialectical evolution and historically has been imposed by schooling (which has led to the eradication of the Northern dialects, „platt“, which are derived from old Saxon and thus are related to English), so it is questionable what its meaning should be in this chart.
Yiddish is a colonial sociolect and somewhat marginal to the evolution, so again, not clear why it was included. IIRC, Koestler wrote in “The Thirteenth Tribe” (where he rejects the mainstream hypothesis of the origin and nature of Eastern Jewry) that Yiddish is based on the South-Eastern variants, not on the South-Western variants.
Looking at the Latin languages, similar inadequacies can be seen. Very superficial and misleading, all in all.
Maybe this chart is meant more to showcase CSS and web graphics than linguistics.