Both loops and branching/dispatching are examples of control flow, which is essentially independent from the 'data flow' default of most "visual programming" approaches. You can actually show both in the same visualization, but only in a well-defined "sub-diagram" sense. That is, a "block" in a data-flow visualization can be defined by a flowchart (showing control flow), and vice versa.
The dual problem is that flowcharts (in the traditional, control-flow-only sense) cannot show fork-join parallelism or fixed point constructions, while both are readily expressible by data flow.
The dual problem is that flowcharts (in the traditional, control-flow-only sense) cannot show fork-join parallelism or fixed point constructions, while both are readily expressible by data flow.