If Ohtani was eligible for the draft he'd be projected to go 1st overall...a team like the Red Sox is seldom, if ever, going to have a shot at drafting that type of talent.
If you want to judge him based on the "hype," that's fine, but I'd rather focus on what he does on the field and whether it's worth the investment placed in him. No, he's almost certainly not going to be the "Japanese Babe Ruth," but he doesn't have to be. I remember when Jose Abreu came over from Cuba there were some similarly hyperbolic statements thrown around - "he might just be the best hitter in the world," one article proclaimed - and while he hasn't turned out to be that, he is a very good player on a fair contract and well worth having. I suspect Ohtani will turn out similarly (though he'll cost much less to acquire) - or he could be an utter bust and never provide any value. Who knows? The bottom line is that the winning team will have to risk very little to find out, which is why you have so much excitement and intrigue surrounding his situation.