People who say "no one" or "everyone" do not mean 100%. That isn't how English works. It's why English provides qualifiers like "absolutely no one", or "100% of people".
Just like if I say "everybody likes ice cream", you and I both know that there's somebody, somewhere who loathes ice cream.
Just like if I say "everybody likes ice cream", you and I both know that there's somebody, somewhere who loathes ice cream.