I will unsay about Correa being no better than Polanco, as far as errors go, but other wise he is lacking especially in range, while Baez is minor league level at short stop with his Rtot and Rdrs numbers this year of 1 and -1 with per yr number of 10 and -13 while Simmons were 14-14 and 16-15 -- Seager came in at 1-0 and -1-0.
Semien's numbers are just as lacking compared to Simmons, and his bat is NO better then Simmons while NONE of them are in the same league of fielding ability as Simmons.