I don't know what happened, but my locales got messed up after a paru update

Your repos are also broken with multilib not being enabled.

I noticed you also mentioned earlier ‘re-enabling’ the cachy mirrors.

Once again .. did you recently ‘manage’ some pacnews (in this case /etc/pacman.conf.pacnew)?
How was that accomplished?
Do you use some sort of script or utility that does any of this for you?

PS.

For the language case please enable a language in /etc/locale.gen either by removing the preceding # or by copying the line to the bottom and doing the same. For example on mine the bottom is;

[...]
# Locales enabled by Calamares
en_US.UTF-8 UTF-8

Then running;

sudo locale-gen
bash -c 'unset LANG'
bash -c 'source /etc/profile.d/locale.sh'

You could then check something like locale again.


For the repos you would need to revisit /etc/pacman.conf and similarly remove # in front of the lines for [multilib] repo.

Then the various lib32 package will be available again and pacman -Syu should work more normally.