You’ve tried “sudo pacman -Syu” and you’ve probably tried “sudo pacman -Syyu” but still Arch is reporting that you’re bang up to date yet no updates have arrived for over a month! No, you’re not up to date in the slightest.
Your mirror has gone stale. It’s not a big issue:
sudo pacman -S reflector
reflector --latest 15 --number 5 --sort rate --country 'United Kingdom' | sudo tee /etc/pacman.d/mirrorlist
You may want to change out that country, I don’t.
Then just do your usual pacman or trizen and you’ll get a flurry of cool stuff.