I could be, but it’s not that easy. Discourse is not a stateless container which is what Google Cloud Run is made for, therefore you’ll need a way to add some kind of Persistent Volume for the data that’s kept in Discourse (uploads, avatars, DB).
I’d use a normal Google Compute instance and that’s it. With some kind of script, or infrastructure management tools you should be able to automate the deployment of a new Discourse instances, this guide Beginners Guide to Install Discourse on Ubuntu for Development might also help you.