Imagine someone earning just within their means of survival how will they save? Even if they try, they will likely end up withdrawing consistently just to meet their daily needs. That’s why I would rather encourage investment instead. At least with investment, there is higher possibility of making some profit when the need for money arises, instead of watching savings lose value to inflation.
I support that invest is more better than saving cause when you're saving your money remains stable and doesn't add much value but investment would add value to your money over time and the longer the investment, the more valuable your money, anyways based on your statement, someone earning within their means would need to look for more source of income so they won't temper with their saving or investment, remember that investment requires long term and patience and if they have have an income that would carter for their investment and necessary expenses then they're good to go.