I have analyzed both 4..c5 and 4..Nf6 lines, and I don't like what Stockfish is suggesting. Sure, they are playable, but are depressing to play from human's standpoint.
Alatortsev variation with 4.f3
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There's also a more dynamic idea a-la-Gruenfeld. While I'm not sure whether it's 100% sound, I also don't see any outright refutation for white.
In the last position note that the piece placement makes it a little different from normal IQP situations. Black is not poised for a K-side attack, but on the other hand the white pieces are not optimally placed for controlling the important d4 square.
1.d4 d5 2. c4 e6 3.Nc3 Be7 4.f3
I find this line surpsrisingly tricky to play against from Black's perspective. Is there a line that is comfortable for Black which does not involve a pawn sacrifice, or giving White a huge center, which is what Stockfish is suggesting!?