i think design patterns are either

  A) a lack of necessary abstraction - or -
  B) a sign of unnecessary complexity

This. I remember reading a definition of a design pattern as "a structured way of working around a language deficiency".

Powerful languages don't force you to decouple your code. Disciplined use of patterns can help.

But all our minds are warped from thinking web programming has to be different somehow from the desktop programming of old, and that concepts like SRP, LoD, and coupling don't matter.

to me, design patterns are how a team designs on the general way of doing a certain activity, and avoid doing it wrong.

maybe unneeded if you are solo, and I agree that "you should know why the best practice is best" but I strongly feel these are very helpful not only for teams, but for learning.