So it appears, #openSUSE retires YaST in favor of Cockpit and Myrlyn. Leap 16.0 beta no longer has it, but it remains in Tumbleweed for now, no longer in development, though.
I've never used Cockpit or Myrlyn, but YaST always seemed to me barely usable.
I remember openSUSE in 00's bragging about YaST as a purely GUI tool for system management, so you no longer need to open terminal, ever. Well, it was somewhat unwieldy back then: long loading screens every time you open settings, somewhat chaotic UX.
Almost twenty years later YaST still remains the same: same loading screens, same necessity to learn tabs and flags and what they do instead of just opening text file and changing things like you do.
Anyway, apart from my ramblings, it's a huge change. YaST always has been one of the selling points of openSUSE, AFAIR. Now it's gone. Hope Cockpit and Myrlyn are better.
https://news.opensuse.org/2025/04/30/leap-16-enters-beta/