fret hand wrist position

i read that you are supposed to keep your fret hand wrist straight. however, when playing on strings such as the E string (the thicker one) and the A string, which are more towards the top of your fretboard (or more towards your head) when you play, it is very uncomfortable and almost impossible for me to keep my wrist straight when playing on these 2 strings. so my question is...is it necessary for the wrist to be straight when playing on every strings? or is it okay if the wrist is bent when playing on strings such as the E (thicker one) and A string? and what is the benefit of keeping your wrist straight?

Where the heck did you hear that you have to keep your left hand wrist straight. It's bending and changing positions all the time depending on what chords and leads you're playing.

Just keep in mind where guitar is concerned that there are no 'rules'.
Just because somebody else (usually a teacher with preconceived notions of what's 'best' for beginner guitarists) says you have to do it a certain way doesn't mean you have to follow that advice religiously.

Hell... a lot of my students tell me their teachers tell them they aren't supposed to use their left hand thumb and to keep it anchored behind the neck. My advice is that's the dumbest thing I ever heard of. There's a whole bunch of chords you can play that can only be done with your left hand thumb holding the bottom E string or muting unplayed strings.

My advice is do whatever feels natural and helps you achieve what you want to do. Over time you'll find the best positions that fit your particular playing abilities. (not everybody has the same hand size and style)

there are alot of rules, like your thumb should be at about the middle of the back of the neck, but generaly those rules don't apply unless you are playing something especialy complicated, generaly fast paced classical stuff. and it's more a habit fomring thing that alot of guitarist try to put themselves in to be able to play it more easily