before ai it was cognitively expensive to be a programmer cuz you had to really use brain cycles for everything, from architecting, to even using the right variable names etc. it was genuinely draining. & if you programmed for a whole day, you were fucking tired. even code reviews required you to think deeply & you had to be aware of the entire code base to some extent too. so not only did you have to have context loaded, you had to do manual inference if you will. ai completely eliminated all of this strain.