NEM, born in 2015, was handled very little. It has experienced incredible growth after 2017. This was due to its unique software architecture. But after 2018, he had a crash again. It is very low in terms of price and transaction volume.
In NEM coin, there is no Mining system, but a Harvest system. Harvesting project means producing blockchain. So it saves electricity and you don't need super computers. However, this innovation does not seem to be preferred by cryptocurrency users. To be clear, the harvesting system is a bit complicated, if the NEM team could make it simpler, this system could improve.
As a result: To be honest, I think this system will disappear in 2021. Every day users leave the system.