Please help. I'm in a bad mode

This is an excellent and massive question!

You are exactly right that the notes are the same for the scales of all three modes through that progression. I completely understand the “why does it matter which one I’m using” question.

Here is why.

For each chord there is a different frame of reference to show the structure of the specific chord you’re playing on.
The mode defines this.
For improvising bass lines, it is absolutely imperative that you build from the correct root note, and establish the tonality by emphasizing the chord tones of the chord you’re in.
If you’re playing in Dmin7, you should be building from D, and emphasizing the D,F,A,C. The notes of the mode (all the even scale degrees of the mode) will help you connect these more important chord tones in a smooth and melodic way, but not all notes in the mode should be treated equally.
Chord tones have the gravity! They are the places to build from and land on in a melodic solo, and they are the structure that needs to be identified and emphasized in a bass line.
If you’re using the wrong mode (building from the wrong root), or noodling in C ionian the entire time, the clarity and specifics of the chord change will be lost.

In a solo, you can get away with this, but it will sound general, noodly, and possibly unconnected to the music behind it. It can get you through in a pinch, but is not ideal.

In a bass line it is unforgivable, because the move from mode to mode as the chord moves is essential to defining the structure of the song and the place in the form of the song.

Holler with any questions! This can of worms is alllll sorts of fun to mess with.

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