Opening explorer is a very basic database tool, and doesn't take into account different move orders to reach the same position.
Strange statistics in game explorer
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Compare this:
https://www.chess.com/explorer?moveList=d4+d5+Nf3+b6+e3&fromGame=1
where 3... e6 shows 2 games 50/50 draw/black
but actually clicking e6 shows:
https://www.chess.com/explorer?moveList=d4+d5+Nf3+b6+e3+e6&fromGame=1
which shows 3 games with 1/3 equal white/draw/black outcomes.
Therefore it seems the first link above should show 3.... e6 as 3 games, not 2.