Yeah, you can't really call any of them generational talents with any certainty. Look at the top picks since Mauer.
2016 Mickey Moniak, of Philadelphia
2015 Dansby Swanson, ss Arizona
2014 Brady Aiken, lhp Houston (didn't sign)
2013 Mark Appel, rhp Houston
2012 Carlos Correa, ss Houston
2011 Gerrit Cole, rhp Pittsburgh
2010 Bryce Harper, of Washington
2009 Stephen Strasburg, rhp Washington
2008 Tim Beckham, ss Tampa Bay
2007 David Price, lhp Tampa Bay
2006 Luke Hochevar, rhp Kansas City
2005 Justin Upton, ss Arizona
2004 Matthew Bush, ss San Diego
2003 Delmon Young, rf Tampa Bay
2002 Bryan Bullington, rhp Pittsburgh
2001 Joe Mauer, c Minnesota
Price, Strasburg, and Harper are the only thee that have been great players. Upton is obviously a very solid talent, and Correa is on the way to being a star. But look how many misses there were in-between. A few others are TBD, but there is such a high bust/disappointment rate at #1. Don't get your hopes up too high, as Wabit said above.