Genuine question

Why on earth MD-11's are still flying in 2025? It's one of my fav aircraft's ever and I understand that airline cargo companies want to use them as much as possible to save money before to order new planes, but where is the safety ? Ofc we will need to wait for the FAA and not speculating, I'm just curious why cargo airlines they still use obsolete/very old aircraft... RIP UPS CREW