There are various ways how you can push in malware to isolated systems (compromised USB drives used to be common, and still seem to work in some penetration tes

There are various ways how you can push in malware to isolated systems (compromised USB drives used to be common, and still seem to work in some penetration tests; but in general, you might succeed in getting someone to deliver a malicious document file to such a system with some zero-day in it. Also, compromised hardware - e.g. ship them a USB mouse that 12 hours after plugging in technically becomes also a USB storage device and a USB keyboard to send commands to install stuff), but then you have the trouble of what that malware should do once on those systems - being able to establish a communications channel is useful in such a scenario. So there's definitely a role for such tools, only these scenarios are relevant only to quite expensive targeted attacks, essentially spycraft by state actors, not for e.g. commercial ransomware operators.