Do any government pensions around the world have a requirement to demonstrate that their financial plan is indefinitely sound? That is, not selling out the viability of the pension plan for future generations.
Where I live (in Australia) the vast majority of "pensions" are funded by individual's regulated superanuation savings (like a 401K?), with the government pension as just a safety net. In our case "selling out" would actually be "stealing people's money", which could theoretically be achieved by tax, but would be ridiculously unpopular and rather nonsensical.
It's not perfect but it means the current young people aren't funding (all) the current old people, so it smooths out the changes in demographics somewhat. And since the superannuation fund might invest internationally, its value isn't necessarily as tied to the national fortunes as would be a bank account with Australian dollars or a governement pension, again buffering against the risks that come with an aging population (and declining economy).
But the pension provider sure can, and indeed usually people don't save enough for retirement.
By definition the current electorate is fine with what they have assumed so far.