i think yes bitcoin will lost forever if owner die.
but if his own relative know the details they can recover

,,,Maybe will lost forever because no-one knows the private privacy key of his/her wallet, But I think the 1M$ is remained stable because bitcoin is a limited stock only 21M$ so, this might easy to trace. Actually,this topic is an opinion only. For nowadays it's impossible to be happened because we are now in a new era that almost educated people. To avoid it happens, let's tell and inform to our family or love ones.