90% or better of them, that is true. One I have had succes with free ranging is silvers. Also seen a lot of other post on here with silvers out. They will roost at night in your trees. They are not going to be like domestic birds at all though. You will never just walk up to them and corral them up like chickens. Some rare cases, you can tame 1 or 2 here and there down, but that's the exception rather than the rule.
Also, even the silvers are a 50-50 shot at it.
With all of them, they are best in pens at all time, most will be gone and never look back.
Mine got out when a storm knocked a hole in the grow out pen on night. It was all male silvers and some various goldens and amherst.
The only ones that were there at daylight were the silvers, never saw the ruffed species again.
Being all males, and they were still there, I said what the heck, lets see what happens. They stayed right there, walking around like all the other oddballs out side.
If you hand raise them with baby chicks, or better yet, let a tame broody hen raise them, most of them will hang around. Their range will be greater than most chickens though. More like guineas. I had a couple of ring necks roamed along with my guineas for a while a few years back. Coons got them when they were setting. (Just like guineas) I have a couple of young ring necks and few guinea keets being raised together now to see if they stay together as a group when I release them.