Just in this thread I have one person saying that I should avoid flakes and you are telling me it will save me. I think we proved my point.

Fair, fair. A slightly more charitable take might be that flakes solve/streamline a set of problems that are particularly acute for power users, and installing multiple specific versions of software without needing to copy the definitions into your overlay is absolutely a power user move.

Flakes are undeniably useful but it's gated behind an experimental flag and documentation work is ongoing. For now, it just shouldn't be the first point of entry for beginners.

The documentation is the biggest gap for sure. I've only been using Nix for about a year, and I'm using flakes exclusively. Although I don't have direct experience with the legacy system, I could definitely picture it being very frustrating managing inputs via the NIXPATH envvar rather than explicitly with flake locking.