I don't consider this telling people what to do with their money, since sending money between addresses in the same wallet is just a technicality. Everyone is still keeping their own money. Consider this: when you spend money from an address, Bitcoin protocol forces you to spend all the money from that address (keeping change by adding another output). Seems similar to me, in the sense that technically you're forced to do something particular with your money, but not really, since it's just details of the protocal that don't affect you (again, similar assuming you can access your prvkeys)

The while word there is important. This isn't trying to solve a problem of people losing their funds, but something different. Unfortunately, in this proposal adds a possibility of losing funds. The point is that erosion is very slow and starts only after a long time, so it should be trivial to avoid any loss whatsoever, and losing very little if mistakes happen (this is assuming you have access to you own prvkey at least once in a while, which now I understand is not valid in all cases).