The default VIM installation in Debian 8 does not have syntax highlighting enabled by default. Other distributions may be the same. Running the BASH script below should enable syntax highlighting.
SEARCH='"syntax on' REPLACE='syntax on' FILEPATH="/etc/vim/vimrc" sudo sed -i "s;$SEARCH;$REPLACE;" $FILEPATH
All the script does is uncomment the
syntax on line as shown in the image below (which also shows you what VIM looks like when syntax highlighting is enabled).