The reason why the Goplus could detect the hack on coinmarketcap was because the hack has already been done. I believe this can only bring to one notice about a recent hack and past hacks and not future hack. Which the hack haven't been done already it wouldn't have notified you. .
Exactly!
The only reason why this tool has detected CMC as a suspicious website is because many users have reprted it as a scam.
It seems like this tool doesn’t act proactively. It warns you against a certain website just because it has received many complaints against it not because it has detected a certain threat. This kind of tools can’t be trusted becase they usually generate many false positves.