If you’re all “Damn the write endurance!” and want the easy install of Proxmox on EMMC(if you still have it), or a janky USB2 thumb drive. I do suggest reviewing the code before you install something from a random github, but we all know that if you’re actually considering this, you’re probably not gonna do that anyway.
https://github.com/HonestGoat/proxmox-ve-flash