By this I mean:
I have no local web server running on 19421; and
Your link doesn't launch or reinstall anything for me.
Now, something I do that most people probably don't is periodically check StartupItems as well as the LaunchAgents and LaunchDaemons folders, so I can remove anything left over.
I do not mean to trivialize this problem, because what Zoom has done here is egregious and unforgivable, BUT is it accurate to say that the reinstall behavior depends on
1, usage of Chrome and
2, the presence of a StartupItem / LaunchAgent / LaunchDaemon?
I ask because it didn't work for me, even though I still had the ~/.zoomus shit in place (obvs, I don't anymore).
I just want to make sure I understand it properly, and that I've taken the necessary steps to prevent Zoom's unwelcome return.