It can run in a container, a virtual machine, hosted on a cloud instance or whatever. Nowadays, you have infinite choices for isolation. One of my colleague runs it in a DigitalOcean droplet and nothing else.
Of course you can do security for isolation on top of it any time, and sure, you won't get security updates after a while which would be nice, but there are tools to secure an outdated app in other ways either.
Not really.