In the same way, learning is not a transient state either. You will always have to relearn. Those impossible barriers that you eventually got through will reduce to speedbumps - but they will always be there, slowing you down. And if you don't use it enough, you'll have to relearn.
Also, be aware that once you've climbed a learning curve, at least unconsciously you are no longer incentivized to simplify it for those who come after. Why reduce the barrier-to-entry for others, after all? You got through it, so why can't they? And this is why generations of kids learn bad music theory, and generations of physicists learn bad particle names. It's important to be aware of this effect so you can counter-act it.
The only reason I'd disagree is if the next source code control system were somehow as much an improvement over git as git was over its predecessors.
> if it can save me the hassle of learning a new one.
Not to mention the hassle of converting all those legacy repositories, converting CI/CD, etc.