Neil looked up pictures of cats.
He first suggested the idea in 1989.
He initially thought they should be neutral, acting as platforms without control or intervention.
Anonymity can bring out the nastiest side of people, as they may say things they wouldn't in person, believing there will be no consequences.
He suggests tweaking the way kudos (likes and shares) are given, rewarding constructive or positive actions more.
Ameliorate means to improve or make something better.
Kudos refers to praise and appreciation, often in the form of likes and shares on social media.