The SysRq or Send system request key on newer Thinkpads, specifically the ThinkPad T14s Gen 6, is Fn - S, see the User Guide for Linux.
But even when /proc/sys/kernel/sysrq is set to 1 I can’t seem to trigger it (other than directly echo h > /proc/sysrq-trigger).
I tried Alt, Fn+S, H or AltGr with various hold, hold-release etc. patterns, but nothing worked.
Changing to a virtual terminal (Alt Ctrl F4 [use F2 to get back into the GUI]) and entering ScrollLock Fn + K does pause terminal output, so that missing key is working via Fn.
Anyone got that working? On 25.04 and Wayland/Gnome.