The protoboard and wire approach can not produce in large scale. If you're building some one-off thing for yourself or just building a prototype, it will be no problem. But if you're building something that you want hundreds of, you will want to use a PCB.

PCBs have lower parasitic inductance and capacitance than a breadboard. And impedance can be controlled for high frequency signals. Circuit density can usually be higher.

The advantages of a PCB is when you're working with higher frequencies, especially up in the RF range, where you start having to worry about crosstalk or inductive coupling, noise, etc., and minute changes in impedance and capacitance become critical factors. In those cases, it's probably easier to build a PCB that takes those things into account.

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