I think the simpler explanation is that good PCB CAD tools are extremely difficult and require a lot of developer effort.
KiCAD is very good for an open-source tool that can produce basic PCBs. However, modern paid CAD tools are on a different level entirely. The differences may not be obvious for simple boards with low speed connections, but it’s a world of difference to use one of the high end CAD tools on a complex board with high speed traces.
KiCAD has recently reached a point where I feel like I can execute most of the designs I want with enough effort expenditure, but the paid tools still make certain tasks much faster and easier.
KiCAD is very good for an open-source tool that can produce basic PCBs. However, modern paid CAD tools are on a different level entirely. The differences may not be obvious for simple boards with low speed connections, but it’s a world of difference to use one of the high end CAD tools on a complex board with high speed traces.
KiCAD has recently reached a point where I feel like I can execute most of the designs I want with enough effort expenditure, but the paid tools still make certain tasks much faster and easier.