First of all, engines aren't great at evaluating openings.
Second, when I enter those moves, Stockfish only gives a very small difference between the two moves -- not enough to worry about. Your e4 is a fine move, as is exd4, or Nc6 (which is what I would play), or even Nd7 if you want to treat it as a reverse Tarrasch. (I'm not immediately seeing what difference the rook pawn push makes. Somewhere down the line, it probably does, but the basic strategies against the French seem like they still make sense. If anything, the extra move by White probably makes it worse than a French, since g4 and g4 have been weakened, which seems more dangerous for Whtie than a potential pawn storm does for Black.)
Ignoring the goofy opening by white here, why would a pawn push to e4 be bad? Stockfish says take the pawn, but in doing so you completely open up the file to your King. It is these scenarios that just confuse the hell out of me....why would I take that pawn and open up an attack when I could gain space as black by pushing the pawn and reduce a square for the white knight to go to?? Not to mention taking opens up white's queen bishop to development. If white counters the pawn push with c4 then I just play c6 to protect the d pawn. Thanks so much in advance.
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