6-string bass tuning vs guitar tuning

[Gio]

@Malyngo

As far as I understand it, it basically goes like this:
Guitar has the tuning it has because of chords, chords are easier to finger with this tuning.

Yes to this.
And because the roles are different and we bass players get so dialed in to our lovely and unchanging tuning-in-fourths pattern, it makes more sense to keep the pattern the same and add more strings than have to relearn all the fingerings for that one string tuned differently.