This does NOT concern the users of
ArcoLinux or Arch Linux
This does concern the packagers
ArcoLinuxB or Carli
Arch Linux decided to change the format of the packaging from pkg.tar.xz to pkg.tar.zst.
I let you read the official message from Arch Linux. See image above.
In the video we will show you need to change the default packaging extension in /etc/makepkg.conf
############### EXTENSION DEFAULTS############
PKGEXT='.pkg.tar.xz'
SRCEXT='.src.tar.gz'
to
############### EXTENSION DEFAULTS############
PKGEXT='.pkg.tar.zst'
SRCEXT='.src.tar.gz'