Mutation mode question

I'm a veteran cf player. I remember when mutants used to have a breathing sound. It's still in the game files

''NanoGhostBreath.wav''

Also titan slugs and dreads use to have an effect where you see they were glowing. For example in 1st person when you were a titan slug (green mutant) you used to see green dust like effect. With the dread it used to be blue

My question is: why did these features get removed? Will we get them back?