ibus is a input method framework which can be used for writing non-Latin characters.
I noticed that the Arch Package for ibus pulls python2-dbus, python2-gobject, python2-gobject2 as dependencies.
python2 is not listed as a dependency of ibus in Ubuntu, therefore most likely it is not needed for ibus to function normally.
Is there a reason why ibus in Arch/Manjaro needs python2?
More importantly, what can we do to remove python2 as a dependency of ibus in Arch/Manjaro?
If it does work with python 3 (like it seems like for Ubuntu 20.10), then the Arch package maintainer needs to know, so you should tell him. Last packager seems to be Jan Alexander Steffens from Arch Linux.
I found ibus-clean AUR which does not have any python2 or gtk2 dependency.
Also, someone submitted patches to the bug report. Hopefully it will soon be accepted.