This guide is copied from a post by @TonghuiMing. https://community.esri.com/t5/arcgis-experience-builder-questions/overwrite-default-map-filter/m-p/1269114
The first option is that you can configure a filter widget with clauses like the following - one clause with a solid none case, like ("OBJECTID=-1"), and not ask for values; then add other clauses that ask for values (they must not contain preset values, being all empty to make it work). Remember to set the logic operator to "OR":
Last but not least, you need to turn on the option "Apply this filter automatically". In this way, you will have the following behavior which starts with none on the map and filter by the desired/input values.
