In Jainism, manushya bhav is still extremely valuable, even in the 5th ara.

The purpose is not only immediate moksha. Its purpose is to:

• Gain samyag-darshan right faith
• Live according to dharma
• Reduce and destroy karma
• Practice ahimsa, satya, aparigraha, and self-control
• Create the causes for a better future birth
• Prepare the soul for liberation when the proper time and conditions exist

In the 5th ara, it is accepted that moksha is not attained in this time period in Bharat and Airavat kshetra. But that does not make human birth useless. Human life is still precious because only in human bhav can the soul:

• understand dharma properly,
• discriminate between soul and body,
• develop detachment,
• and stop accumulating very heavy karma.

So the real purpose of human birth is spiritual progress. Even if liberation is not possible in this ara, the soul can still move closer to liberation by pure conduct and right belief.

A simple way to see it:

• Moksha may not happen now
• but the path to moksha is still being built now

That is why Jainism calls human birth rare and meaningful.

If you want, I can also explain this from the point of view of karma, time cycle, and the value of samyag-darshan.