Nix / NixOS

You are free to set up such a project, instituting yourself as the initial dictator, accepting merit challenges of some specified form, and see whether someone bothers to go for your jugular. Call it KingOfTheHillOS.

...in all seriousness the general issue with merit-based approaches is that you need a way to decide on what "merit" means, and to have an actual project and not a one person show you need a community that shares that definition, and you can't dispose of the dictator if they have the power to dictate what merit is, so you are left with either a) an unchanging definition which is just as bad as unpatchable software or b) some form of stakeholder democracy.