…kind of.
I got rid of yast2 but after the latest zypper dup many yast2 packages got installed.
How do I keep my system permanently ‘clean’?
When one wants a package blocked from being installed by being a dependency or part of a pattern, it can be tabood.
YaST > Software > Software Management. The Search for the package. When installed, uninstall it first. When uninstalled, Right-click on the package and then choose for Taboo - Never install.
When it is Yast that you want to remove, then you cannot use Yast to lock it after you have removed it. So maybe “zypper al” to add a lock. Try
man zypper
for details.
I assumed that someone who wants to live without YaST has made himself fluent with the usage of tools like zypper. Enough to be able to look at it’s man page. And thus I thought that the hint that something like tabooing/locking exists would be enough.
In any case, I was too lazy to look it up. 
Although I replied to your post, it was really intended for the OP.
After posting, it occurred to me that maybe he only wants to be rid of the Yast GUI. He might still be using Yast ncurses, perhaps in a command-line only setup. I’m not sure how intertwined are the GUI and ncurses versions.
In this case:
zypper al yast2-control-center
should do the job.
Another thing is, that I don’t understand the desire to remove it. It will only be installed when a desktop role is chosen during install. If a (headless) server role is chosen, only the ncurses versions will be installed. If that also is removed, one has removed on of the most beautiful tools openSUSE / SUSE provides.
Quite curious about the reasoning behind this, and whether YaST was removed entirely.
I did dnot pay much attention to his “get rid of” and “clean” as if YaST is a plague. I just tried to answer the technical question. without understanding the background of it. Maybe not the right attitude.
This is the German subforum, maybe better in the English one.
So closed temporalily.
Reopened again.
Oh boy, I did not even notice. Thanks for moving.