I think you are seeing it as a software developer as opposed to (say) a biologist on the first year of their PhD who just wants to keep their scripts safe. Mercurial's strong point (IMO) was to cater to the 90% of developers who work with two-to-three colleagues on a single branch - you could always make things more complex if needed (as evidenced by Firefox doing just fine), but the defaults were always more user-friendly than git's.
For a more time-appropriate critique, this post [1] from 2012 gives an overview of what working with Git felt like at the time when git was being popularized as an alternative to Subversion (including a frequent comment of "use Mercurial instead!"). It's also worth noting that git's error messages have become more helpful since - while the documentation for git-rebase used to be "Forward-port local commits to the updated upstream head", it now reads "Reapply commits on top of another base tip".
Software developers will be the vast majority of users though, at the very least for the CLI.
Git certainly isn't anywhere close to the prettiest thing for ease-of-learning (and indeed used to be even worse), but Mercurial didn't seem particularly good either. Really for the common uses the difference is just needing to do a "git add ." before every commit, vs a "hg add ." before some.
All of my git usage has been on projects with ≤2 devs (including me; technically excluding a few largely-one-off OSS contributions of course), but I still use a good amount of local temp branches / stashes / rebasing to organize things quite often (but also have some projects where all I've ever done is "git add .; git commit -m whatever").
For a more time-appropriate critique, this post [1] from 2012 gives an overview of what working with Git felt like at the time when git was being popularized as an alternative to Subversion (including a frequent comment of "use Mercurial instead!"). It's also worth noting that git's error messages have become more helpful since - while the documentation for git-rebase used to be "Forward-port local commits to the updated upstream head", it now reads "Reapply commits on top of another base tip".
[1] https://stevebennett.me/2012/02/24/10-things-i-hate-about-gi...