For example having models of capacitor and resistor you can put them together in schematic. Which in turn can be a part of the bigger design. Then test it in simulator. That's how Simplorer works. Alternatively you can write the code in VHDL or Modelica. But visual is quicker, easier, and more reliable.

Obviously it works well for UI, was used for decades now.

As for the rest,... there are visual programmers for robots, mostly for kids.

HDLs rule for gate and transistor level circuit design. I don't know what major PCB houses do but I'd be horrified to discover that 16-layer boards still have a visually built schematic producing their netlist: just finding the right pad on 256BGA components would be awful, let alone finding what else is connected to that net.

Schematics aren't supposed to scale. They're a lossy representation of a subcircuit without caring about the intricate details like footprints or electrical/electro-mechanic constraints.

PCB designers largely don't use HDLs because they don't really solve their problems. Splitting a BGA component into subcircuits that have easily legible schematics is not hard, but it's also not what they care about. That shit is easy, making sure the blocks are all connected correctly.

Verifying the electrical constraints of the 256 pad component is much harder and not represented in the schematic at all. They need to see the traces and footprint exactly.

As an example, the schematic doesn't tell you if a naive designer put the silkscreen label and orientation marker underneath the component which will cause manufacturing defects like tombstoning in jellybean parts.