It depends, but generally yeah, its a crock.
Same with paddling.
Most kayakers can't self rescue, and that's just crazy.

With the right partner, I could definitely do more with the partner than I am willing and able to do alone. Without the right partner I am unable to do as much as safely solo.

My daughter is a great hiking buddy though. She is only 9, and small, but we are almost able to do as much together as I am alone, at least on land and in summer. She is learning to sail, and to paddle, and to cross-country ski, so in a few more years she will be there, and a few more after that if we still travel together now and then we might be able to do some adventures that I might not do solo. We shall see. It's more likely that she will go here own way, and that's ok. There is always solo.