Vacuums are nothing like what they were in the decades past - Dyson has transformed them entirely - maybe not 'every decade' but they are evolving.

Go and use a fridge from 40 years ago and compare to a modern one - granted, their essential function has not really improved that much. They were much more durable before, but rudimentary.

Most product categories in tech have evolved, and it's why there are leaders in most categories.