How to understand?
Is
"society towards the next century"
related to
"ageing"
or to
"to cope"
?

Yes, "society towards the next century" is related to "aging" or to "to cope". What this sentence is saying is that Japan is now focusing on an economy based on what the consumer (the common shoppers) want, and they need to do this because the younger generations won't really care about the economy in the next century.

This was most likely written before the year 2000 because the Japanese reads 「２１世紀」 which means "21st century".

Thank you very much for your explanation!

>This was most likely written before the year 2000...
This was my guess...:)

> So they need to do this...
before the 21st century will come, if I understand you correct (?)

and
if 「２１世紀」 means "21st century", maybe this information should appear in the tranlation? What's your opinion?

"So they need to do this..." Yes before the 21st century.

Now that I think about it, "21st century" would sound better in the translation.

This sentence is terrible and terribly disorganized.

I think this sentence is trying too hard to show off, and doing so, it defies grammatical rules (for instance, the sentence should end after "aging society").

P.S.
The two English sentences are not equivalent.