Etcher stuck on starting screen on MacOS Catalina

[peter40b]

Without looking at your Etcher-dump.log, this seems like exactly the issue I had dealt with hear:

Can't create boot stick or card

My suggestion: check in System Preferences > Security & Privacy > Privacy… scroll down the list of parameters on the left to “Full Disk Access” and then add BalenaEtcher.app (by finding the app in the Applications folder). Be sure to select the checkbox to the left of the app name. I have BigSur. I also added Disk Utility.app so I could make disks.