Hi @kishorek1264980,
I have seen that in prior version of AEM 6.4 (eg: AEM 6.4.2), components without cq:design_dialog node are allowed in layout container while editing the template policy. However in later version, it is updated to not allow such components without cq:design_dialog node and now in structure view, only components with cq:design_dialog are allowed when editing the template policies. Just check if it is related to this use case.
Thanks!!