It’s nonsense to assume that every vote for Stein in 2016 would have voted for Clinton. Most exit polls showed that people who voted for Stein or Johnson would not have voted in the first place. Hillary was a losing candidate from the start.
Good thing you don’t need to assume that every vote for Stein would have voted for Clinton… Are you not understanding the numbers there? In Michigan, the number of Stein voters was ~5x the margin of victory. FIVE TIMES.
And 7 times the margin of victory left the presidential spot on the ballot blank in Michigan, if stein wasn’t on the ballot they would’ve just gone there. People did not like Hillary, blame her for that not stein.