These effects are very specific, and are usually only relevant in their respective meta
It is exceptional against many combo decks stopping them going off outright and will tend to get in a few extra pings against most decks however it is ultimately just a 3/4 in most situations, particularly with the decline of combo
Playing Xorn on curve is a mistake unless you are creating treasure tokens by attacking with a creature like Hoard Robber, or are casting an Instant that turn which produces a Treasure token
Tomorrow Bruce Richard will take up the challenge of listing his Top Ten cards from his guild of choice, followed by Mark Wischkaemper, Jason Alt, and then Abe Sargent closing out the series this Friday
Then when an opposing artifact dies, every Ape and Monkey you control, including Kibo, gets a +1/+1 counter on it
Paying 2 life to have them come in untapped helps you to stay on curve, and in decks like Death's Shadow, that life loss is actually a bonus