I'm not the hugest fan of My Neighbor Tororo - the film - (proceeds to get booed off any and all social media platforms this opinion ends up on) but when the character of Totoro showed up in this, I think it was honestly more exciting than the famed Andrew Garfield stepping out of the ring scene in Spider-Man: No Way Home.
Mei and the Kittenbus is another Hayao Miyazaki short that's good for some bite-sized Ghibli, but not able to do for the short film format what his best films do for the feature film format. It's like listening to a song you really like from a great artist versus listening to a complete, expansive, and entirely whole album from that same artist. The quality's still there in many regards, but it's never going to be quite the same impact-wise.
Still, Mei and the Kittenbus is worth digging up if you can, but that's easier said than done. Honestly, all these Studio Ghibli Museum exclusive shorts would make a killing if they were compiled into one DVD or Blu-Ray set; I know I'd buy that stuff, and I imagine the Miyazaki shorts and any other high-profile ones would all fit onto a disc or two. That might make people less-incentivized to see the museum, but I guess to that point, I'd argue it just feels a little unfair that people all over the world love Miyazaki, yet the only way to see most of his short films is to live in Japan (particularly near the museum) or have the money to travel to Japan to see the museum, which is becoming increasingly hard these days, what with the cost of... everything.
I don't know; that's my maybe selfish view as someone not living in Japan, but a boxset of these interesting short films and other oddities would sell pretty well, I imagine.