NEM used to be in top-10 for many years. It is sad that it paid the price for the Coincheck exchange weak security. It started droping from this moment and never recovered.
Actually I was incredibly impressed at how well the price held. I would never have expected such a thinly traded coin to weather 10% of the available supply being dumped but it did.
This is the culmination of the total indifference people feel towards NEM. It's never gained a proper toe hold with developers or traders. A bear market just rams that home ever firmer.