I've found it to be a ton easier than RPM or deb files. Not much ceremony - a binary can sometimes be packaged with a dozen lines of config.
The problem isn't that it's not easy. It is easy. The problem is that it's an entirely new ecosystem and language, and takes time to learn. But it's worth it.
Don't expect to run anything that isn't packaged. Don't expect packaging some binary blob for NixOS is easy.