Fedora Silverblue. But since Fedora aims to include telemetry (although in a reasonable way) by version 40, I’ll switch soon to something else. I feel it might be time to give BSD an honest attempt.
I just hope we get more immutable distros by then.
There already are a few: itsfoss.com/immutable-linux-distros/ and Ubuntu seems to work towards an immutable future as well, I think it’s where most distros well be in a few years. The transition needs time though.
12 Future-Proof Immutable Linux Distributions

Immutability is a concept in trend. Take a look at what are the options you have for an immutable Linux distribution.

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