He was a businessman, who hired people to invent things. He was certainly useful, but it's always been surprising to me how much credit he got for inventing things.
To a tiny universe of Reddit/XKCD readers perhaps.
In the rest of the world, for example at the offices of Con Edison, or in the city of Edison, New Jersey, he's still considered to be somewhat important.
There's a billion and one things one could mention about Tesla. Sadly, only the tiny universe of people who dislike Edison (and see him as a businessman, not an inventor) are aware of Tesla's contributions.