You can't push on the map and get an outside angle on the enemy team because you will just hit the fence or run straight into a kick.
And there's not enough room to stab and move enough distance to not get stunned on the edges, so it turns the groupfight from one based on pushing and kiting, into who has the lowest ping to not get stunned and who can not attack first. This limits the different styles you can play in a groupfight.
The black lines show where I can move on a bigger map after I stab to not get stunned, as you can see I have many options, which makes it very hard for the enemy to be able to stun me, now on the smaller map, I can only go straight back, or back and to the left(from the POV of the picture) if I go straight left I'll run into my teammate and clump. This makes it very easy to get stunned, because when you stun someone you have to guess where they are going, and the map has narrowed the options down from 6 to 2(according to the picture).
To not get stunned you have to maximize the distance between your player model and the enemys bayonet after you stab to have enough time to recover from the stun, and you maximize the distance using angles.
You can't use angles because the player already knows where you are going to go. You have taken the skill out of not getting stunned and its now based on an innate quality(ping). Whoever can recover from a stun the fastest(which is entirely decided by ping) is the one who doesn't get stunned.
Very little kiting or pushing happens on these maps, just each team lining up straight on. This map limits the styles and tactics you can use and thus renders some players styles obsolete.
TLDR: Map heavily favors low pingers need to change the map