I think there is an ideal grip width for each pulling/rowing angle. For pull-ups and pulldowns, it will usually be slightly wider than shoulder width. I don’t really like close grip pull-ups or pull-downs (the only thing I feel more are my biceps and forearms). Pull-ups/pulldowns are best suited to hit the armpit region (teres major, teres minor). I think it’s suboptimal to try and use pull-ups and pull-downs to emphasize hitting the lower lats (you often see people try and do this with underhand grip pulldowns). There are much better exercises to achieve that such as 1 arm dumbbell rows and supinated grip seated cable rows.
For barbell rows, the ideal grip width will usually be a little narrower. I prefer the wider v-grip handles for t-bar and seated cable rows.
TLDR: when it comes to back training, yes you want a variety of exercises as it relates to pulling/rowing angles. However, there is usually an ideal grip width for each pulling/rowing angle.
I think single arm dumbbell rows with a slightly staggered stance (usually performed over a dumbbell rack) are one of the best horizontal rowing exercises. There is no other horizontal rowing exercise that confers a better stretch in the lats. There are also many degrees of freedom for you to find the form that hits your (lower) lats the best. How much grip pronation? How staggered of a stance? Stance width? Row to belly or hip? How bent over do you want to be?