Illustrator Script - Batch Export Symbols as SVGs

ExportSymbolsAsSVG.jsx

var doc = app.activeDocument;
var symbolCount = doc.symbols.length;

if (symbolCount >= 1) {

    if (confirm("Are all your layers hidden?")) {

        // choose directory
        var dest = Folder(doc.path).selectDlg();

        // folder chosen
        if (dest) {
          
            // create temp layer
            doc.layers.add();
            
            // create temp artboard
            doc.artboards.add(doc.artboards[0].artboardRect);
            
            // get temp artboard
            var tempAB = doc.artboards.getActiveArtboardIndex();

            // loop through symbols
            for (var i = 0; i < doc.symbols.length; i++) {

                // place a symbol instance - temp
                var symbol = doc.symbolItems.add(doc.symbols[i]);
                
                // resize artboard
                doc.artboards[tempAB].artboardRect = doc.visibleBounds;
                app.redraw();

                // choose directory
                var filename = doc.symbols[i].name;

                // export symbols
                saveSVG(dest, filename);

                // delete temp symbol instance
                symbol.remove();
            }
            // remove temp layer
            doc.layers[0].remove();
            
            // remove temp artboard
            doc.artboards[tempAB].remove();
        }
    }

    function saveSVG(dest, filename) {
        // save options
        var type = ExportType.SVG;
        var options = new ExportOptionsSVG();

        // file
        var file = new File(dest + "/" + filename);

        // export
        doc.exportFile(file, type, options);
    }

} else {
    alert("You don't have any symbols in this document");
}

Note: This script seems to have issues since Illustrator added dynamic symbols. I wouldn't recommend using it.