At the end the issue has been resolved simply uninstalling a plethora of
Qt packages and then reinstalling it in small groups just for restoring
the normal usage of my system, I.E. the Yast Qt...
That's interesting, from the brief look I had at the WSJT-X's compilation help I saw some QT requirements. But now it's hard to tell what's what since we don't know whether the recompilation may have helped or not here.
So I really haven't discover the precise cause of the SIGSEGV of wsjtx
but it was certainly been caused by some of the "Qt" packages that after
I uninstalled.
Well, next time will be armed with knowledge.
Personally I like to use systemd-coredump, since it automates/make things easier to analyze coredumps, it downloads the required debuginfo packages so GDB's backtrace are meaningful, aside from information about the shared libraries involved when the core that got dumped.
You can take a look at those resources to get some basics about SIGSEGV + GDB:
http://www.unknownroad.com/rtfm/gdbtut/gdbsegfault.html and https://www.baeldung.com/linux/segmentation-fault
Those may give you a bit of an idea of what possibly went wrong with WSJT-X.