Stick with NixOS. A declarative config will save your ass down the line if it hasn’t already. If you have any interest in programming or IT in the future, the skills you learned will prove invaluable & once you get the hang of it, making modifications & patches will start to feel a lot safer as you can keep pulling updates while your patches still apply. Nix is still going to be one of your better options if you want to avoid the snap/flakpak space (I do not blame you). As for corporate control, something will either fix the Nix foundation from the core or a community-controlled fork will usurp it with probably almost no changes for an existing Nix install just like these things have always sorted themselves out with time (or join the Lix or Aux spheres if you want to actively fix the situation now instead of waiting if it really bothers you).
If you need help, ask in the official Matrix room or Discourse—I can only imagine the spam & bad takes from those residing in a proprietary, data-siphoning Discord chatroom.