"How many legs does a dog have if you call the tail a leg? Four. Calling a tail a leg doesn't make it a leg."
Abraham Lincoln, 16th president of the United States.
Misinformation, disinformation, or fake news in today's parlance, is not new, it's been around as long as people have.
Does it really matter? It does really matter.
Acting on, re-posting, or just claiming something to be true you are not certain is true, suggests you are lazy.
Doing any of those things knowing the basis for your claim is not true, suggests you are a liar.
As President Ronald Reagan repeatedly said, "Trust but verify"
("Trust but verify" is an English translation of the Russian proverb Доверяй, но проверяй taught to Reagan by Suzanne Massie, American author of the book Land of the Firebird: The Beauty of Old Russia, and advisor to President Reagan regarding his negotiations with Mikhail Gorbachev, then President of the Soviet Union.)