Talking toys saw something of a heyday in the 1960s-1970s. The technology was still relatively novel, and it added an exciting play element to action figures.
The early-mid 70s in Japan also saw explosive growth in the variety and popularity of tokusatsu (live action) and anime TV shows like Kamen Rider, Barom 1, Mirrorman, Mazinger, and many more.
Sofubi figures were the toys of choice, probably because they were inexpensive to produce, but there was also an enormous variety of vehicles, daily goods (including hero-themed shoes!), and a lot more.
Talking toys were certainly at the higher end of the cost scale. Not only were fewer made, but far fewer have survived. So, seeing a collection like this in their original boxes is something special.