Take the database and add-up all the wins ...
Example small sample: 1. d4 e5 is best for white.
1. e4 e5 (If 2.Nf3 ...) = WDL (30-50-20) Best for Draw
1. d4 e5 (If 2. dxe5 ...) = WDL (62-22-15) Best for White
1. c4 e5 (If 2. Nc3 ...) = WDL (30-45-25) Best for Draw
1. Nf6 e5 (If 2. Nxe5 ...) = WDL (80-0-20) Best for White
Average 1. ... e5 (If using the above) = WDL (51-29-20) = Lower rated would include the draws (White 81 vs 49 Black) = difference of 32
1. e4 e6 (If 2. d4 ...) = WDL (35-41-23) Best for Draw
1. d4 e6 (If 2. c4 ...) = WDL (36-40-24) Best for Draw
1. c4 e6 (If 2. Nf3 ...) = WDL (35-42-23) Best for Draw
1. Nf6 e6 (If 2. c4 ...) = WDL (39-40-21) Best for Draw
Average 1. ... e6 (If using the above) = WDL (36-41-23) = Lower rated would include the draws (White 77 vs 64 Black) = difference of 13
1. e4 c5 (If 2. Nf3 ...) = WDL (32-42-25) Best for Draw
1. d4 c5 (If 2. d5 ...) = WDL (45-29-25) Best for White
1. c4 c5 (If 2. Nf3 ...) = WDL (36-47-17) Best for Draw
1. Nf6 c5 (If 2. c4 ...) = WDL (31-45-23) Best for Draw
Average 1. ... c5 (If using the above) = WDL (36-41-23) = Lower rated would include the draws (White 77 vs 64 Black) = difference of 13
The lower rated vs Higher rated player would include the draws percentage in their preference of 1. e5 or e6 or c5.
Now you see 1. d4 ... is best for white, if the other responses are best. Soon or later the best moves cause draws. So stop while you are ahead in best moves and make the plan happen, with a not so best move. Make a curve like a curve ball, in the best moves to win the game. Taking the best move may be best when playing fast, but not in slow time controls. The engine best moves end up having a tunnel vision effect assume every move is a best move, which is rare.
The more general move that gives more options to win, is really the best move. Assume the opponent will make at least one imperfection and that general move style will make that imperfection look like an error.
Example small sample: 1. d4 e5 is best for white.
1. e4 e5 (If 2.Nf3 ...) = WDL (30-50-20) Best for Draw
1. d4 e5 (If 2. dxe5 ...) = WDL (62-22-15) Best for White
1. c4 e5 (If 2. Nc3 ...) = WDL (30-45-25) Best for Draw
1. Nf6 e5 (If 2. Nxe5 ...) = WDL (80-0-20) Best for White
Average 1. ... e5 (If using the above) = WDL (51-29-20) = Lower rated would include the draws (White 81 vs 49 Black) = difference of 32
1. e4 e6 (If 2. d4 ...) = WDL (35-41-23) Best for Draw
1. d4 e6 (If 2. c4 ...) = WDL (36-40-24) Best for Draw
1. c4 e6 (If 2. Nf3 ...) = WDL (35-42-23) Best for Draw
1. Nf6 e6 (If 2. c4 ...) = WDL (39-40-21) Best for Draw
Average 1. ... e6 (If using the above) = WDL (36-41-23) = Lower rated would include the draws (White 77 vs 64 Black) = difference of 13
1. e4 c5 (If 2. Nf3 ...) = WDL (32-42-25) Best for Draw
1. d4 c5 (If 2. d5 ...) = WDL (45-29-25) Best for White
1. c4 c5 (If 2. Nf3 ...) = WDL (36-47-17) Best for Draw
1. Nf6 c5 (If 2. c4 ...) = WDL (31-45-23) Best for Draw
Average 1. ... c5 (If using the above) = WDL (36-41-23) = Lower rated would include the draws (White 77 vs 64 Black) = difference of 13
The lower rated vs Higher rated player would include the draws percentage in their preference of 1. e5 or e6 or c5.
Now you see 1. d4 ... is best for white, if the other responses are best. Soon or later the best moves cause draws. So stop while you are ahead in best moves and make the plan happen, with a not so best move. Make a curve like a curve ball, in the best moves to win the game. Taking the best move may be best when playing fast, but not in slow time controls. The engine best moves end up having a tunnel vision effect assume every move is a best move, which is rare.
The more general move that gives more options to win, is really the best move. Assume the opponent will make at least one imperfection and that general move style will make that imperfection look like an error.