Looking at his statistics, I don't get it.
Big K numbers (31.0%), low walk numbers (4.8%), fine average (.269) and some good pop (.208 ISO). Adds up to a 106 wRC+ in 200+ Daytona PA. Defense doesn't seem to be his calling card.
That power potential must be something, because those numbers look pretty run-of-the-mill to me. The MLB Prospect write-up seems to be more bullish on his defense than Fangraphs, and I suppose all those offensive numbers play up quite a bit if he's a SS (or even CF). Sounds like he's got some pretty high-end speed as well, though it doesn't seem to produce a ton of stolen bases.
Don't get me wrong, hope he's a star, but I'm a bit confused just doing some cursory internet digging.