SAPUI5 sap.m.list in a popover is emtpy when populated using bindElement

I have a table (sap.m.table) with different columns. One columns contains a link and when the user clicks on the link a popover fragment opens and shows some details in a list (sap.m.list). The data is coming from an oData Service. One Entity feeds the table and through a navigation property the data for the popover is fetched.

I have a working example for this scenario where I create the the list template in the controller. But I believe that this should also be possible just by xml and a bindElement in the controller. What is the mistake in my second scenario?

First Scenario (which is working fine): Popover XML:

    <Popover
    showHeader="false"
    contentWidth="320px"
    contentHeight="300px"
    placement="Bottom"
    ariaLabelledBy="master-title">
        <Page
            id="master"
            class="sapUiResponsivePadding--header"
            title="Aktionen">
            <List
                id="AktionList">                    
            </List>
        </Page>
</Popover>

Calling the Popover in the controller file (sPath is /TableEntity('123456')/AktionSet):

if (!this._oPopover) {
Fragment.load({
    id: "popoverNavCon",
    name: "bernmobil.ZPM_STOERUNG_FDA.view.AktionPopover",
    controller: this
}).then(function(oPopover){
    this._oPopover = oPopover;
    this.getView().addDependent(this._oPopover);
    
    var oList = Fragment.byId("popoverNavCon", "AktionList");
    var oItemTemplate = this._BuildItemTemplate();
    oList.bindAggregation("items", sPath, oItemTemplate);
    this._oPopover.openBy(oControl);
  }.bind(this));
} else {
    var oList = Fragment.byId("popoverNavCon", "AktionList");
    var oItemTemplate = this._BuildItemTemplate();
        oList.bindAggregation("items", sPath, oItemTemplate);
    this._oPopover.openBy(oControl);
}
_BuildItemTemplate: function(){
        var oItemTemplate = new sap.m.ObjectListItem({
            title:"{AktionsBez}", 
            type: "Inactive"              
        });
        
        oItemTemplate.addAttribute(new sap.m.ObjectAttribute({
            text : "{Aktionstext}"
        }));
        oItemTemplate.addAttribute(new sap.m.ObjectAttribute({
            text : "{path: 'ChangedAt', type: 'sap.ui.model.type.DateTime'}"
        }));
        return oItemTemplate;       
    }

And this is the idea of the second scenario which is calling the oDataService but not displaying any data: Instead of having only the List definition in XML also the ObjectListItem is defined in the XML:

<List
    id="AktionList"
    items="{AktionSet}"> 
    <ObjectListItem 
        title="{AktionsBez}"
        type="Active">
        <ObjectAttribute text="{Aktionstext}" />
        <ObjectAttribute text="{ChangedAt}" />
    </ObjectListItem>
</List>

And in the controller instead of building the template and doing the bindAggretation there is just:

var oList = Fragment.byId("popoverNavCon", "AktionList");
oList.bindElement(sPath);

How do I get the second scenario displaying data in the list?