No, not necessary.
Before they were domesticated chickens followed a cycle. The hens would lay eggs and raise chicks in the good weather months when food was abundant. When days got shorter in the fall they would stop laying eggs and use the nutrition that was going into egg production to replace their worn out feathers. They would molt. When the better weather returned and the days got longer they would resume laying eggs and raising chicks.
Then we domesticated them a few thousands of year ago. We started selective breeding them to lay more and bigger eggs, grow bigger so they had more meat, or just because some are prettier, the decorative breeds like Polish or Silkies for example. Instead of them going through cycles of plenty of food and times of not so much, we feed them regularly often really well. Some people might even provide warmth or light in winter. The basic instincts remain to stop laying and replace feathers when days get shorter and crank it back up when the days get longer but for some those instincts are weakened some.
Because of domestication and how we manage them, some (not all but some) pullets will skip the molt their first winter and continue to lay all winter and until the following fall. This is not a big deal. Nothing to worry about. Practically every hen will molt her second fall as the days get shorter unless you extend the lights to trick her into not knowing the days are getting shorter.
After the hen has laid a pretty long time she needs to molt to recharge her system. Each individual hen can be different but it's usually more than a year of constant laying before they hit this point, sometimes well over a year. The number of eggs they lay can drop off. The quality of the eggs they lay can deteriorate. Some may start the molt earlier than others. Some may just do a partial molt. The cycle of a pullet starting to lay in summer and continuing to lay until she molts the following fall works out pretty well.
Some people mess with this "natural" cycle by extending lights. They can wind up with a partial or full molt any time of the year. Periods of stress can trigger a molt, often partial but sometimes a full molt. The basic idea of the molt is pretty simple, they replace worn out feathers in the fall when raising chicks would be a challenge, but as it always is with chickens, there are exceptions and things that can make it more complicated.
I think what they are calling a soft molt is that some chickens are fast molters and some are slow molters. That has nothing to do with how you feed them. It is controlled by genetics and has nothing to do with how fast the feathers grow back. It is about how fast the feathers fall out. A fast molter's feather fall out in a hurry and the chicken can look really bare. Those photos above show that. A slow molter will loose its feathers slowly. Often you can't tell by looking at them that they are molting that feather fall out is so slow. About the only way you can tell they are molting is that you see some feathers flying around. I prefer the fast molters, they get it over with and may return to laying much earlier.
There is more to it than this, always is with chickens. The way we feed them and manage them some hens may lay a few eggs while molting. Hens may even go broody in winter.
The bottom line, quit worrying about it and enjoy your chickens.
