SO different! It can be alarming.. and even makes me worry some for every molting bird.
That difference was tremendously diminished when I learned about using (Purina) Flock Raiser with oyster shell on the side for active layers instead of "layer" feed. My ladies, even the head lap lady would become stand offish and avoidant.. as noted by the other poster.. pin feathers can be quite painful.
Despite being only about 2-5% digestible in their raw form, feathers are made from 90% protein and its amino acids. Layer feed is typically the bare minimum required nutrients to keep a light bodied bird like leghorn in lay. Dual purpose birds like Rock, Orpington, Marans, etc do better at 18-20% protein. While birds not in lay like molters, broody's, and juveniles, or roosters do not need the calcium offered in layer feed but can't avoid it. (long term *could* cause issues like gout, kidney failure, or death though there IS a genetic component to that) Since my flock is often mixed age and/or gender (and even species in the past).. I use flock raiser full time. It is pricier because protein is pricier. But the difference seen was well worth it.. TO me. Surprisingly since making the switch (several years ago).. the ladies (that do so regularly but didn't) NOW still come around and hang on my lap even during molt! Your mileage may vary.