> 30%

Thats not accurate. The estimate is about 2 billion in 25 years.

https://www.who.int/news-room/fact-sheets/detail/ageing-and-...

We also have models for how that works at a country level because we have countries that have far exceeded that.

And the vast majority of 60 year olds are still self sufficient and economically productive.

Average global retirement age is around 65 and in most countries it’s creeping towards 70. And percent of world population over 70 looks much more manageable over the time span we can realistically model.