The ZoomScale property fails to set zoom scale for the selected search result from LayerSearchSource.

Solución alternativa

Instead of setting the ZoomScale property, update view.scale or view.zoom in a 'select-result' event of the Search widget. For example:

   searchWidget.on("select-result", function(event) {

    view.goTo({

     scale: 500000

    });

   });

For more information, refer to ArcGIS JavaScript API/4.14/API Reference: Event Details.

Pasos para reproducir