I'm torn on this issue. I think the elderly and people in general should get a decent life, but on the opposite side we have Europe that's investing massively more in making its boomers richer and more comfortable than anyone in human history has ever been(average pension in France is now higher than the average salary), rather than investing that money in ensuring opportunities and prosperity of future generations, who are facing economic stagnation/degrowth and are forced to foot the bill for this elderly spending, with the guarantee the pyramid scheme they're funding will fail them when their turn comes to benefit from it.
So perhaps Japan sees the defense capability those 150 F-35's bring to its future national security more valuable than keeping the elderly alive for a few more years.
Yeah, it sounds harsh when you look at people like that, but taking care of people takes resources(money), and money is finite, so all these decisions are a game theory trolley problem, where you have to choose whose lives a country should prioritize the most: the past generations, or the future generations.
Historically in the history of nations would be willing to sacrifice the elderly to prioritize the survival and growth of its future generations, that was the social contract of the tribe, that is until the western boomers came and decided they deserve to fuck the future of their nation if they can get wealthier and feel good till the end.
I'm not saying there's one correct solution here, because I don't have it. I'm saying tough decisions have to be made from which there will be winners and losers, so a nation should choose the winners carefully, if it wishes to have a future.