See: https://archlinux.org/news/wxwidgets-32-update-may-need-manual-intervention/
Remove wxgtk2 first and then proceed with the upgrade answering “Y”.
Edit
Ah, you did the upgrade answering “n” already?
Remove wxgtk2: sudo pacman -R wxgtk2
Then replace the other two: sudo pacman -S wxwidgets-common wxwidgets-gtk3 (Answer with “Y”)