Yep, but I'd also count some package managers which have learned from Nix but chosen a slightly different path by relaxing the requirement of 'purity', or leaning harder on containerization features.

Besides the ones I mentioned in my reply which is a sibling to yours, I think the package managers for Haiku and RedoxOS fall into this category (but I can't be sure! I've never used them, so my memory of how where work is likely to have gaps).