It is about enclosures.

That would be a double hedge :-P

The term "vorgesetzt" refers to the fence, i.e., you may enclose with a hedge and still place a fence directly on the boundary in front of it. This is important, for example, for animal owners. Apparently, this is prohibited on public areas here.

However, in my opinion, the 1.20m only refers to the enclosure adjacent to the public traffic area ...!?

Regardless of the actual meaning: you can agree with your neighbors about what you plant on the respective side. And if someone insists strictly on the maximum 1.20m, I would simply plant trees/shrubs (at the permitted distance! Observe applicable statutes!) instead of a hedge to provide the appropriate privacy and sun protection.

The "placed in front" refers to the fence, i.e., one may enclose with a hedge and still put a fence directly on the boundary in front of it. This is important, for example, for animal owners. For public areas, this is apparently prohibited here.

The 1.20m, however, in my opinion, only refers to the enclosure toward the public traffic area ...!?

No matter how it is actually meant: one can agree with their neighbors on what to plant on each side. And if someone insists strictly on the maximum 1.20m, I would simply plant trees/shrubs (at the allowed distance! Observe applicable regulations!) instead of a hedge, which provide corresponding privacy and sun protection.

This is how I also read it – that it only refers to the access side here. Everything else is also regulated in neighborhood law/right.