Even kang Daniel, who was at the top with both general public and big fandom support, couldn't have a successful solo. Male solos don't really have a market it's just fun time with their fanbase and money grab. look at beakhyn and d.o they become less relevant with less buzz right now with exo being inactive and split and their solos make no noise outside their decreasing fandom compared to karina who is a female and still active with her group she has the support of both fans & public and has alot of buzz

So riize members are better to stick to each other for as much long as they can it's their best option wether they are the most or least popular active groups always get more attention and buzz wether for solo work or as a group.