I was a Leon fan way before it was cool but hold your horses.
Anderson, Wonderboy, Adesanya, Pereira, Volkanovski, even O'Malley.
These are strikers off the top of my head who have outstruck good/great strikers and have multiple finishes on their records and generally do more damage to their opponents. Hell I might put Gane over Leon. Just because he doesn't get hit as much doesn't make him better than the above.
Now if we're talking about striking based fighters with the overall best MMA game then Leon has a better case. It's rare to see a skilled striker with such great defensive grappling and clinch game that he can shut down the likes of Usman and Colby. It's his well roundedness that makes Leon great imo. But pure striking? He's damn good but has a lot left to prove.