You can fly from the Ruhr area to the Balearic Islands, but not by bike for a weekend in a hotel in the Sauerland.
Nobody understands that.
Ms. Illner's guests don't understand this either, but it complies with the applicable rules.
Because of the low incidence values, the Balearic Islands are no longer a risk area, so you can go there without restrictions.
It is that simple, although it is undoubtedly difficult to understand.
Of course, one could now discuss the logic of such rules.
But nobody did that on the show because it could ruin the pandemic political fetish of incidence values.