732 available updates cannot update system

Seems like you have unsupported packages installed, creating a dependency problem.

But without the real output we cant really know.

Maybe you could share with something like

sudo pacman -Syu > pacoutput.txt
curl -F'file=@pacoutput.txt' https://0x0.st

Which will send the file to the 0x0 pastebin, and provide you with the link.
Share the link here.

System info can be retrieved by

inxi -Farz

And similarly sent to 0x0 with

inxi -Farz | curl -F 'file=@-' https://0x0.st

I will also include a guide with tips like how to format code..