NoMachine essentially made themselves irrelevant by not upgrading their client software often enough, IMHO. I was using all sorts of VNC hackery to make it fast and loved NX, but it was weird and niche (never worked quite right on the Mac) and still slow when compared to RDP and Citrix, so the rise of Ansible and other sorts of automation blew it out of the water for server management.

For end-users, Citrix was just way better, even if more expensive, and there was no compelling reason to switch...