probably the syntax was wrong
Variable assignment values must be enclosed in double or single quotes if they include spaces, semicolons or other special characters outside of A–Z, a–z, 0–9.
source:
https://man.archlinux.org/man/os-release.5.en
Edit:
try the following changes:
NAME="Arch Linux"
PRETTY_NAME="Arch Linux"
ID=arch
BUILD_ID=rolling
ANSI_COLOR="38;2;23;147;209"
PRIVACY_POLICY_URL="https://terms.archlinux.org/docs/privacy-policy/"
LOGO=archlinux-logo
IMAGE_ID=archlinux