From what I can gather (people don't reply to my enquiries), the data in the graphic was invented by a few German rail enthusiasts. I've struggled to find any information that it's a wide spread interpretation (even in Germany). In the GB discussions no one had any comprehension of it. It's ridiculous to determine the busyness/size of a station by "where trains can change from one track to another track."
There's so much wrong with that graphic:
Misunderstands what a siding is. 
Almost all (all?) multi-track stations have crossovers nearby.
A nearby junction has no bearing whatsoever. 

You'd have thought this page would mention it:
https://en.wikipedia.org/wiki/German_railway_station_categories 

@phodgkin What is the officially agreed demarcation line between a halt & a station? Name one that you perceive as a halt, but if the criteria you use to determine it increased slightly would make it a station? Likewise, name a station that would become a halt if your criteria reduced?