Wrapping git is essentially a flawed idea; there are just too many corner cases (rebasing, resetting etc) for a wrapper to handle them all.
I also remember having some issues with Arcanist on Windows.
For example, if you merge a reviewed commit into two different branches and then god forbid you try to merge those two branches, Arcanist will fail with a cryptic message - and you'll only realize that this is arbitrarily/buggy-ly forbidden only when you try this workflow several times...
Vanilla-git or even a Bitbucket/GitHub/GitLab style pull-request style workflow gives you so much flexibility that Arcanist just takes away from you, and the only way to learn these quirks is the hard way....
Whereas gitlab/github etc are much more flexible, but also slower to use and more demanding that your individual developers adhere to your standards.
I think Phab is best for projects of 3-5 to 50 (basically until your project is dealing with multiple commits per hour and no single repo is going to be painless), especially when you have new team members and you'd rather let the the tools enforce the workflow as opposed to policing them yourselves. However, if you don't like that workflow, you're never going to be happy with Phab.
Finally, Phab has some really nice features that I haven't seen elsewhere, like posting lint errors inline in the merge request.
Arcanist is not a Git wrapper - you can (and should) use Git normally. All Arcanist does is automate the process of creating and uploading patches, and applying remote patches.
The `arc` command did rewrite my branches, ruin my revisions or otherwise do something buggy a handful of times, particularly with `arc update`.
It's completely fine and quite useful for someone to say that their experience was bad with a tool in general on an internet thread about the tool in general.