That last thing means that if someone goes on a campaign to smear someone's name deliberately and starts digging up any information that can be found and recklessly publishing it without checking it out, it could be considered libelous, even if true.
Reckless disregard would mean you don't care if they statements are facts or not. And that by putting false information in with facts, you want to mislead the reader/listener. If all items were fact, then a compilation of all items would still be truth and is an absolute defense (in the US). As soon as you make (knowingly) false statements that a reasonable person would believe, only then can the defamed begin to have a case (in the US).
The important part is "a reasonable person would believe them true".
The US has the strongest free speech laws in the land when it comes to defamation. (Because in order to protect the right to dissent, you must protect the right to criticize).