https://gitlab.synchro.net/main/sbbs/-/issues/973#note_7607
Looks like an illegal instruction in AppKit, which implies an OS issue. You could try running in curses mode from a terminal, or updating your SDL version though.
--- SBBSecho 3.29-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)