I don't think jujutsu is proprietary (unless you want to redefine that term). Source is freely available, and it uses Apache License 2.0.

While you're right about the disadvantages of git, pretending that it became ubiquitous because it "became a quasi-religion because Linus made it in a day" is selling short its advantages. If you think about it for even just a little bit, it should be obvious what a simplistic statement that it. Also, git was not the stagnation you make it out to be. Even with its warts, it was a breath of fresh air, not unlike jujutsu is now a breath of fresh air vs git.

I remember working with SVN, and all things considered, git was a vast net improvement. Git took a lot of pain away. It made working with a versioned code base faster and simpler, to the point of enabling much better collaborative software development. There's a reason we got GitHub and not SVNhub. And GitHub was what helped git become so dominant.

Would it have been better if Mercurial had beat out git in the propularity contest? Possibly? There's trade-offs between the two, but Mercurial's easier interface counts for a lot. But if it had won, I'm sure we'd be griping about its shortcomings by now.

So yeah, I'm also happy to see some movement around the ergonomics of version control, but I don't understand the need to disparage the tools that got us where we are. It just seems that you're more bitter than happy, and like you're letting that bitterness cloud your judgment.