There Is No Longer a CyanogenMod
The CyanogenMod project along with other custom ROM or firmware images to replace Android have served their purpose. Cyanogen Inc. was founded in September 2013, in an attempt to commercialize CyanogenMod. The CyanogenMod project was shut down in December 2016. The CyanogenMod developer group and Cyanogen Inc. agreed to forking the CyanogenMod code into a new project named LineageOS
Did the CyanogenMod project end because of the commercialization?
I don't think so. Yes, there were arguments about licensing (Apache vs GPL vs closed-source components), and about acknowledgement and compensation from the new corporation to programmers. But if those were the only reasons, the new LineageOS project should be much more prominent than it is.
I think that CyanogenMod and the other custom ROM / firmware projects were victims of their own success in a way. They had, perhaps surprisingly, accomplished the goal of getting feature sets into Android.
Most of the features that led people to replace Android with a custom ROM were now available in Android. There was little reason to install a custom ROM.Linux and other
open-source project LineageOS
The cyanogenmod.org site has been shut down, although you can still view it at the Internet Archive.