I’m using Leap 15.2 with KDE atm, and systemd-coredump was not installed by default (same as the tools to go with it). And I didn’t do anything special to avoid installing it either. Strangely, gdb was installed by default, so indeed, the missing coredump facilities may well be a bug
And tbh, that doesn’t surprise me all that much. How many current users would know what a coredump is, let alone what to do with it? (20 years ago, it was a different story, seems the efforts to get Linux into the mainstream have had some effect…)