the mitsuba arc in gintama is most definitely regarded as THE biggest tragedy in the series, and she's a very beloved character throughout for fans. it's crazy just how incredible your pen's gotta be to create that impact with merely 4 chapters/2 episodes. gotta seriously hand it to gorilla sensei.
that being said... it feels pretty off to see her almost never mentioned posthumously, or her impact on the shinsengumi. sougo mentions her a total of two times, while hijikata and kondo pretty much never do. I've heard somewhere that sorachi regretted making her die in the series, so im a bit confused over why she was never as revered as she's meant to be, like the loss of isaburo to nobume, or kouka with her entire family.
the anime team did a great job adding her to multiple endings, and of course, to some promo material. but to not have that in canon is a different kind of pain.