The line suggests the opposite yes. That's why I take issue with it.
There's nothing easy about nix. Maybe flox makes it easier, but I am so burned out by screwing around for countless hours with nix I'm not even going to try to figure out if it's true.
The fact that my experience with nix has historically been _so_ difficult, I fear even something that claims to make it "easier" will not be able to deliver -- my aversion has everything to do with nix, and little do with any product which claims to improve it. Consider it guilt by association.
For me, it doesn't simply need to be easier, it needs to be usable. I lack confidence a product which is an abstraction layer is going to solve that for me, because I have a personal inability to understand the underlying system.
Maybe you need to try it out rather than casting doubts about a product you haven't tried yet? Pre-emptively doubting claims based on your past experience with a tool Flox claims to solve seems like a poor way to go here.
For what it's worth, there are a number of options in the Nix space that really do solve for its complexity like Devbox and now Flox.
If you still use it, my best suggestion is to use a github search for 'path:.nix TERMs' when you run in to issues. It's likely someone already has that custom package, or an overlay to fix that missing compile option, or whatever else it is that you're looking for. I find reading other peoples solutions also helps with understanding and solving related problems.
I'm in no means claiming Nix is perfect, but coming from other distros to NixOS I really appreciate the ability to reboot to a new generation and then reboot back if I run in to issues. To do the same in Arch I had a bunch of 'snapper plus manual steps' to accomplish the same.
Is that the line you are referring to? Sounds like the opposite of what you suggests it says.