Age matters because in many cases the house was built with some expectations, and something else won't work at all. In the 1950s your house got a total of 4 circuits, which was enough for clocks and lights, one fridge, and a kitchen mixer (an electric range was an option and added circuits). Of course TVs arrived in the 1950s (they existed before then but were not common) and started blowing power budgets. As people started using more electric new houses got upgraded to handle those loads, but many older houses have not been updated as it is expensive (major remodel as you need to tear down walls).

Of course the above is standard, not everyone takes the standard. However it is unusual to take something else.

Builders (read electric codes) build for what is common uses. If everyone wants an something that uses a lot of power the wires will be made to handle that in new houses. However if you want that same thing in an older house you may discover that the rewiring needed makes it not worth it and so you look for an alternate.