I haven't tried it on a Nexus, but I did that with my Nuvinci. I worked fine except that I had trouble finding a front derailer that worked because the chainline was pushed out further than most derailers wanted to go. Nexus chainline should be a little closer.

24 sounds really low. I'd be worried about how the hub would handle the torque. Depending on your cog size.

I ended up removing my front derailer. I would manually move the chain. Ride around town on the big ring, push it to the small ring when I was loaded up. Then I got lazy. Haven't used the big ring in a long time. Running 18/36 on my Alfine 8, same as I was on my Nuvinci. High end is missing a little. Low end could be a little lower, but for the most part it's fine. But I have no mountains.

Now I'm moving to bike with horizontal dropouts. One aspect of that I'm looking forward to is ditching the tensioner. Once that happens, there's no chance to use the big ring.

Long term I'm considering a Speed Drive: a bottom bracket based 2-speed set up. Once chainring, but still possible to switch to high gear. Until then, I think I'm good with the set up I have. But, yeah, mountains could change that.

So, sure, you can do it. I would make sure your high end and low end are useable. Might be worthwhile to bring the rings closer together in size rather than to have one ring you just never use.