Yeah, US model is that we prefer independent living for seniors as long as possible, then living with family, and only then assisted living (not that it always goes that way, but that tends to be the ideal) at which point not enough seniors in assisted living are capable of helping others for the Japanese model to work.
It’s a bit of a chicken-egg problem in the US—we try to keep seniors out of assisted living because it’s incredibly expensive and has a reputation for poor quality; those things are the case because they require lots of paid labor, but also don’t pay great, resulting in high costs but also often-not-great quality; so seniors who have other options tend not to enter assisted living, so capable seniors aren’t around to do any of the work that might reduce reliance of the system on paid labor…
It’s a bit of a chicken-egg problem in the US—we try to keep seniors out of assisted living because it’s incredibly expensive and has a reputation for poor quality; those things are the case because they require lots of paid labor, but also don’t pay great, resulting in high costs but also often-not-great quality; so seniors who have other options tend not to enter assisted living, so capable seniors aren’t around to do any of the work that might reduce reliance of the system on paid labor…