Melee fighters are not weak in League because of no turn time
For like 4 seasons, it were melee fighters who were dominant class in league. Yeah, each team had a marksman, but it wasn't unpopular to have multiple fighters in one team, and having your marksman to be actually useful for anything other than tower-busting in many metas required dedicating 2 or 3 champions to protect them. Insisting on something being inherently wrong with LoL's system in favor of ranged champions is silly.
Ranged toplaner always was a simple trade off(that often wasn't worth it) - ranged gets to bully in lane, melee provides his team with actual frontlaner, usually yielding in far superior composition, both when it came teamfights and splitpushing. Broken stuff that messed with that balance, like Ryze's infamous Red Ball of Doom Taking 1/3rd of My Health Every Time I Lasthit were consequently - albeit not always swiftly - dealt with.
Melee tops are very weak right now because season 6 introduced several BS ranged champions reworks (Graves, Quinn, Kennen), as well as items and masteries that favor ranged champions(Fervor[especially coupled with Hurricane], Youmuu's, to lesser extent TLD), meaning that strong mid-to-late advantage melee toplaner should have often isn't there.
Those problems are being dealt with right now on PBE. Fervor is gone, replaced with mastery far less oppressive in lane. Greenfather's Gift is concerning, but three new resolve masteries should still tip the scale in most matchups in favor of melee champions. Renek, Irelia and the like with CotC should be able to easily punish ranged toplaners. Youmuu's is being shifted towards assassins.
TL;DR
Stop whining, you are pathetic.
