since @r expands to site:reddit.com, it's intuitive to expand -@r to -site:reddit.com
Examples:
laptop -@a -@e
shows laptop results excluding amazon and ebay
diy ideas -@p
remove pinterest for diy ideas
silksong reviews -@yt -@r -@stcm
finds dedicated review articles
"supply chain economics" -@w
to find articles/papers rather than a wikipedia summary
