@JonB additional info: if I close the traceback, Pythonista hangs. If I remove it from memory, wait some time and restart it, the Pythonista startup hangs with a black screen until I power off my iPad.
And no ObjectiveC log, nor @dgelessus faut_log.
Édit: same problem without any run of any script, weird. Even if started from safari or with safe mode setting.