Yep, that’s me. When I first encountered this expression it seemed very strange to me (not exactly ambiguous since I guessed the meaning). I envisioned a plot, with a steep curve: x is time, but what’s on y? You see, there are no mountains where I’ve grown up…
Eventually I’ve come to think of it: x is pleasure that you will be able to extract from the game, y is amount you have to learn to extract that pleasure.
But now I do not think much when I hear the expression. “Steep learning curve?” - ok, I know what you mean. Changing the meaning to its opposite would cause me a great confusion, bigger than the first one.