Since the standard land value is used for property tax, hopefully the decision-maker about the standard land values is himself a landowner in the municipality. This might also explain why SLVs are lower and updated negligently.
Well, that has only been changed recently, I mean starting from 2025 the SLV will be used for that AND the tax office will probably take a closer look then. But that is definitely no reason for "low" standard land values!
The fact is simply that it is difficult to really reflect the market value in the SLV due to the often few purchase transactions. Since a single "overpriced" sale is usually not initially taken into account, yes, it is kept in view, but there are simply zones where hardly anything is sold. But yes, it is also true that the SLV is rather "conservative". However, there are also areas where the SLV almost maps the market value 1:1, it becomes difficult in zones with few transactions that are additionally sought after or that "overnight" become very sought-after zones (displacement effects).