We all gave up moments before hitting the gold. To ultimately disable the ribbon when switching language with shift+tab, you need to insert this into cmd:
REG ADD HKEY_CURRENT_USER\Software\Policies\Microsoft\offi ce\16.0\word\disabledshortcutkey list /v KeyMod1 /t REG_SZ /d 18,4,16
or create a .reg file with
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\offi ce\16.0\word\disabledshortcutkeyslist]
"KeyMod1"="18,4,16"
This works as of February 9th, 2024. The decade long question has finally found its' answer. We may rest now, my brothers and sisters.
This solution works for all office products.