Yeah, he's nothing special other than big power. A better version of Randal Grichuk.
Yes, but the other side of the equation is an 18 yr old that is at best even odds to even make the show in any sort of real capacity, and I'm being really kind with "even odds". Taking a quick scan through A ball statistics for 18 yr olds who have put up comparable numbers and you've got 2 other prospects (Patino & Green), Knapp (arm fell off), Erbe (arm fell off), Tim Collins (5'7 reliever), Taijuan Walker (yuge bust, arm keeps falling off...was the hype best prospect of 2015), and in fairness, Madison Bumgarner.
If we include 19 yr olds just to get a bigger sample (but keeping in mind of course that it's harder to do it at 18 against A ball comp than at 19) since 2006, we get this list:
Will Inman: Thumped at higher levels, 0.0 WAR
Jake McGee: Converted to pretty dominant reliever, 7.0 WAR
Clayton Kershaw: ****ing legend, 64.4 WAR
Tyler Robertson: Converted to reliever, sucks. -.5 WAR
Trevor Cahill: K's didn't carry through the high minors, carved out okay career despite arm falling off regularly. 9.9 WAR
Danny Duffy: Uber prospect that didn't pan out. Okay MLB career, 14 WAR to date. Arm kept falling off.
Benino Pruneda: Last seen as a reliever in the mexican league, 0.0 WAR
Trevor May: Former top 100 prospect, got beat around as a starter, converted to decent enough lateish inning reliever, 4 WAR
Julio Rodriguez: Never threw an inning above AA. 0.0 WAR
Shelby Miller: Another uber prospect with arm physiology that would violently stop working at times. 7.4 WAR
Cody Buckel: Never threw an inning above AA
AJ Cole: K rate didn't carry through the high minors, journeyman MLB reliever. 0.2 WAR
Jose Fernandez: Stud, don't drink and boat. 14.5 WAR
Noah Syndergaard: Stud with ongoing arm issues. 17 WAR
Clayton Blackburn: K rates did not carry into the high minors, 26 and stuck at AAA
Tyler Glasnow: Was looking awful busty, Tampa might have fixed him and then broke him. Currently on 60 day DL with "forearm" issues. 2.3 WAR
Yoel Mecias: Never threw an inning over A+
Lucas Sims: Might be good, probably isn't. Was one of those hype beast prospects who flopped but might still carve out a career. 0.2 WAR
Alex Reyes: Another hype beast. Has thrown 7 innings in the show since 2016. If he can stay healthy he might be elite. 1.0 WAR
Lucas Giolito: One of the most hyped pitching prospects of the last 5 years, looked like trash until this year. But this year does in fact count. Looks like a pretty good #2-3 this year. 2.8 WAR total so far, short of exploding arm syndrome, this will go up a fair bit.
I'll stop at 2014 because no one moving forward has made the show yet from this demographic
Throwing the whole bag together, there's definitely 4 (Madbum, Kershaw, Jose, Noah), probably a 5th (Giolito), and maybe a 6th (Duffy) that are worth passing on a 24 yr old ~2.5 WAR (Zips projection) OF.
Don't fall into the trap of falling in love with super young pitching prospects because they look great in A ball.