This show is mostly famous in English-speaking spaces for being "that magical girl anime where she gets hit by a toy company's truck and dies". There is a whole story behind that-- director mutiny against the toy sponsor-- but also, now that I've seen a few episodes, it's not exactly out of character for this show. Even these early episodes demonstrate a certain wry, irreverent sense of humor that must have flown over little kids' heads and gone right to the nerds in the audience.
The other story I read about Minky Momo, so many years ago I can no longer source it, is that it was the anime that inadvertently set the standard of Japanese otaku paying ridiculous money for home video releases. In the early 80s they weren't doing box sets of TV anime for consumer purchase, but you could rent the tapes and they were priced for rental: (back in the day, and this includes in the states, "priced for rental" tapes would be 100 or 200 bucks).
Anyway, otaku liked this show so much that they simply called up the rental places and asked to buy their tapes. The price? Who cares, this is Minky Momo we're talking about! It seems to mirror the brony phenomenon, but 30 years earlier, in Japan.