If you did a tag import into a fresh install, instead of upgrading or restoring a backup, that OPC UA server name might be incorrect. It’s “Ignition OPC UA Server” by default in 8.x, not “Ignition OPC-UA Server” (no hyphen).
I think Phil may be on to something with it requiring Edge Compute… this is ringing a bell but I can’t remember if there’s logic in Ignition to allow this particular script even without compute or if this turned out to be a corner case not supported on upgrade and the fix ended up being “complain to your sales rep” and see if you can get a free compute plugin on your license.