No, I actually issued the command as specified in the title of the post:
conda install -c pyviz holoviz
per instructions for holoviz
I eventually got it going, by creating the holoviz-tutorial environment.
But, this was after trying to get it installed in a clone of the base environment that I was successfully using for other things. Trying to install holoviz in that environment also appeared to cause corruption in the base environment even though that’s not where I was installing it. Ultimately had to uninstall Anaconda and reinstall. It’s surprising how many failures conda has when solving a clone of the base environment when installing a new package. I know it’s a different subject and there are probably technical problems causing it to perform so poorly, but I fear having to install anything with conda now after several experiences like this. Not trying to offend, but Conda is getting bad.