Just a very wild guess: I just remembered that because of the 4K display, I once ago have changed the console font from the standard FIXED 8x16 to larger Terminus 12x24 using dpkg-reconfigure console-setup. This font is then also used during boot. Maybe the non standard font (or it's size) is included in the potentially buggy systemd's terminal size calculation and also is a trigger for the bug?
$ dkpg-reconfigure console-setup $ cat /etc/default/console-setup # CONFIGURATION FILE FOR SETUPCON # Consult the console-setup(5) manual page. ACTIVE_CONSOLES="/dev/tty[1-6]" CHARMAP="UTF-8" CODESET="Lat15" #FONTFACE="Fixed" #FONTSIZE="8x16" FONTFACE="Terminus" FONTSIZE="12x24" VIDEOMODE= # The following is an example how to use a braille font # FONT='lat9w-08.psf.gz brl-8x8.psf'
