Multiple Docker VMs or a Single Docker VM?

I went down the "isolation" path when I set up Docker, creating 4 VMs: ARR, Plex, Services, and Sandbox. The function of each should be obvious. (The VMs are hosted on Proxmox VE.) While they admittedly require more management and resources, my intention was to keep groups of services separated so that bringing a service or groups of services down won't impact other services. But thinking about it now, all services are Docker Containers in separate docker-compose.yaml files managed through DockHand. So consolidating to a single VM (and maybe a second for a sandbox) might be just as doable. I don't want to overthink this, but then again, I'm starting to get tight on overall resources, so consolidating would definitely free up some. What do you think?