Yes, but it's hard not to reach his potential when he was already at such a high level from like 2004. He wasn't like someone like Greenwood, Januzaj that needed to improve, Rooney from a young age was at a consistenly high level throughout his career until he started to decline in the early 2010s.
Players like Lewandowski had greater longevity but give me a young Rooney any day.
I think Ronaldo blinkers people's opinions a bit - Nani suffered from that too despite being a supremely talented player.
Rooney at 18 was wildly inconsistent. Greenwood has been far more consistent than him.
Rooney was a wrecking ball though, capable of demolishing opposition through a combination of raw skill and raw power like few we have ever witnessed.