"Essentially they are reducing home computers to games machines."
I guess that for many who are commented here they were "excellent toys to learn how computers worked" - but for many, many others they were just games machines.
They replaced consoles for some time probably because games were much easier to pirate - and maybe even because owning a personal computer had some "cool" factor, and parents saw them less as a pure game machine only.
It's no surprise later pure game consoles became a big market again.