I think the controversy stems from the handling of the chicken and the potential for injury/illness, for basically no reason, not from the actual color.
If I stress one of my girls by restraining her, or manipulating her, or washing her down to her skin (incredibly unnatural) and washing away the oils that protect her feathers and herself, I want to know I have a good reason: bumblefoot, a fracture, a deep or bleeding cut. Thinking she might be cuter if she was pink doesn't constitute a good enough reason for me.