As per official Doc, invoking table.setData() with no parameter is allowed. The doc says,

If you have already set the URL using the ajaxURL option in the table constructor then you can trigger a reload of the data at any point by calling the setData function without any arguments.

However, in the @types/tabulator-tables, the signature of setData enforces to pass at least one parameter which is:
setData: (data: any, params?: any, config?: any) => Promise<void>;

Link to tabulator official Doc
Link to type signature source code