Murena or Iode aren't about development or customization, it's about being able to actually buy a phone and use it without Google services, no tinkering. You might not be the audience, you might have other criteria for what constitute privacy, but basically if you can AND want to install a custom ROM, you are not their market.
None of the actors you mentioned, e.g. LineageOS, AdGuard, MullVad, SeedVault, and all the other "OS" in the name, etc do that so it's not relevant. I'm not saying they are not important but it's a different product entirely.