I also have a freezing kodi on raspberry 4. The Linux is still available and I can log on to the system. In case I can provide logs please let me know. On the first glance, the log files are rather unspectacular.
My suspection is that the video decoder breaks as all freezes on our side happened during playback or pause.
It's a libreelec 9.2.0 with tvheadend for satip playback.