Trump is a bad panderer. He tried for the Sander's supporters and failed, now hes trying for minorities. I guess he could be trying to win back some moderate Republicans but that base is only so big. I also think these Trump supporters are getting too excited and buzzfeed is overselling it.
It's all about the independents. Independents and centrist-leaning Dems and Pubs make up the large majority of the nation. Win independents and swing voters, and you win the election.
Obama lost independents voters in 2012.