He's still a 6'8 power forward. How many of those guys go top 10? He's a David West clone who went in the teens despite being one of the best college basketball players of the last decade.
Maybe you're right, but David West has outperformed his draft position. Also, when an undersized player excels in college it's not uncommon for even the professionals in the business to underrate the guy because of weaker competition.
If you're this height and succeed in the Atlantic Coast Conference you get a lot more credibility than the same performance will earn you in the Atlantic 10. And again, D Will doesn't just have good footwork, he has incredible footwork. If he develops West's mid range shot he'll be a star at the next level, even at PF.
Steve