opening - In the Queen's Gambit Declined, why is 5.e3 so much more popular than 5.Nf3 after 1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Bg5 Be7? - Chess Stack Exchange

To me it seems that both moves transpose into each other in almost all lines, so why is e3 so much more popular? Some statistics from the lichess masters database: e3: 3,289 games (72.5%) Nf3: 877

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Queen's Gambit Declined is probably Black's most solid response to 1.d4. This opening is especially effective when White has already committed to Nf3.

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