Avi; whether or not it applies in general in EY is indeed a machlokes; rav chain kanievsky however, says that lechol hadeos Israeli law doesn’t enjoy the status of dina demalchua, because it is an illegitimate country; a shmad-heretical state in EY is not valid.
As for it applying to other matters besides mamonos, that’s a machlokes without a clear psak one way or the other; I don’t think we pasken that dina demalchusa can apply between yidden when there’s a conflict with choshen mishpat simply because even if such shitos exist, the baal din would have a kim li on the other shitos for sure