The diet manipulation throughout a pre contest diet, along with training and cardio is MUCH harder than any powerlifting routine. I've done both, I've trained both and its not even close no matter what your personality is.
If that were the case, 90% of my clients wouldn't be cutting. Being a bodybuilder goes against your genetic makeup. You are not supposed to have a large quantity of muscle with low bf%. You are basically fighting your genetics (and evolution) at every step.
I could easily increase my strength without putting on much size MUCH easdier than retaining my muscle whiel achieving 4-6%.
What is even easier is getting very big and strong. Eat a lot, and incorportate a powerlifting routine. Problem solved.
You can't just say I'm cutting calories and lifting lighter and expect to be on stage. The manipulation of diet and training is a complete lifestyle that limits you to not having much a life other than bodybuilding (talking about competition)