Thank you Hans-Joerg for your reply.
So you say that this inconsistency is okay? We have 1.x bindings that need manual configuration (even though it is not clearly stated that this is a 1.x binding). We have native 2.x bindings that do things through the UI. And we have in-between bindings that do half UI and half in a .item or .cfg file.
There are two ways to solve it. Either make it consistent or clearly mark a binding as 1.x or in-between and make sure there is a good manual with examples on the web. Something I accept in a beta-stage is trailing behind.
Maybe we have to wait on a final position in this discussion https://community.openhab.org/t/oh2-ideas-to-help-advanced-users-to-create-config-files/12284 as well.