While administrator access is needed to execute a Bashware attack...
I'm not a big Windows guy - I only use it when I have to at work and the systems are administered by the IT staff... But it seems to me once an attacker has admin rights, pretty much the entire machine is his/her playground. I'm not seeing anything startling about being able to screw up a machine via this or that once you're an admin on it.
Yes, with administrator rights you can do just about anything you want to do on that Windows computer, but these “things” will be detected when a malware/virus detector is run on the system. But with this new exploit the admin rights are used to install the malware under the linux subsystem whose processes are not currently monitored by many of the popular malware/virus detection products. This allows the malware to remain undetected and continue doing its evil work while your protection software still thinks everything is hunky-dory. These products will be updated shortly to monitor linux subsystem.