The ChromiumOS distribution CloudReady was discontinued some time after Google acquired the company that offered it. The successor is ChromeOS Flex but there don't seem to be any official virtual machine images available.
The CloudReady OVA file mentioned in the knowledge base article is available on the Wayback Machine (direct download).
$ sha256sum CloudReady-Home-v83-x64.ova
7e4c7304c4b7363dfd778d3a58765c4d03fcd9fb3a1e5ae97c2582b42e4b66ad CloudReady-Home-v83-x64.ova
The version of the CloudReady OVA is actually fairly dated. The virtual machine image was created using CloudReady 83.4.4 and the last released version seems to be CloudReady 96.4.6, which is available on the Internet Archive.
If you'd like to run CloudReady as a VM, you can do so using VMware applications on Linux, Windows and Mac including VMware ESXi, VMware Workstation, VMware Player, and VMware Fusion. We've prepared a CloudReady: Home Edition image as a VMware OVA file to make it easy to import and get started.
CloudReady will not work with Virtualbox as a host-application due to graphics incompatibilities
CloudReady 83.4.4 ChromiumOS in VirtualBox 6.1.40 on macOS 10.15.7 (hangs on boot screen, see above)
On macOS Catalina download and install VMware Fusion 12.1.2 and ahem find a personal license key somewhere.
CloudReady 83.4.4 in VMware Fusion Player 12.1.2 on macOS 10.15.7 (seems to work fine)
