uninstalling an old version

[Karl Berry]

    Then rm -rf texlive/2019 removed
    too much, leaving me with a broken system. 

Bob, what do you mean here? That removal shouldn't affect anything
except TL'19. It's always worked for me.

    So what is the correct way to unistall neither not enough
    nor too much of 2019?

Sorry, I don't know what this means either.

tlmgr remove --all and rm -rf should (after the change I just made, see
my reply to Denis) be equivalent, both removing the entire system
directory containing the TL installation. --best, karl.