Many of the villains seem to have what must have been considered pretty advanced technology at the time: massive energy cannons, powerful magnets that grab passing comets and giant robots that rob banks and jewelry shops.
The machinery is clearly pre-digital (it was the 1940s, they probably couldn’t have anticipated what we have today just as we probably can’t anticipate what our technological capabilities will be in 60 years) and more about dials, levers and tubes. Its all a bit like this machine I found in our doctor’s waiting room:
While the cartoon villain’s machines were elaborate, threatening and seemingly immensely powerful and, at the same time, massive and cumbersome. We have tremendous technological capability in our pockets, far beyond anything that was in use in the 1940s, and we can do and learn more about virtually any topic than anyone could hope to do back then. Just the same, these old machines with all the work that goes into making them do things has a certain mechanical appeal.