Lethality is fine

Or, more precisely, "learn to itemize counters".

Most of these people just keep building the same strait AP/AD builds, never touching a defensive item, then wondering why they keep blowing up to max lethality builds.

Flat armor pen is designed to blow up unarmored targets.

All you have to do is weave a bit of armor and health into your build and you will frustrate any flat lethality stacking assassin.

Lethality as a stat and the items like Ghost Blade, and Edge of Night are fine but the itemization of them is not.

Long Swords are too cheap for their usefulness. The reason why Lethality is here to stay is because most AD users can purchase them when ahead or behind and expect immediate combat stats.

You can win a duel and get a double kill but that 600G does not mean anything when the enemy AD can purchase a long sword to match yours.

There is no item for 500-600G that gives better stats than Long Swords. So your both even. That is why both teams purchase Lethality based items. It is good when ahead and when behind.

Even if your opponent has 1300G and purchases a B.F Sword, you can purchase (3) long swords for 1050G and build them into a Ghost Blade, Edge of Night, or Dusk Blade. A 10 damage difference is nothing. These items will give you more power before they can complete their I.E or E.R.

Furthermore, the components of B.F Sword items are awful. A fully built Lethality item is a lot stronger than a 80% unfinished I.E.

Because you have to remember, Lethality makes you do more damage through armour pen. B.F Sword loses to Lethality because 10 Damage does not equal 20 Lethality, 60% of that 20 Lethality is immediate combat stats, the other 40% scales with levels.

So it is not a Lethality problem, it is a itemization problem. It is either they lower B.F sword prices, increase Long Sword prices, nerf stats or make Lethality items built out of more expensive items.

It is basically ADs are doing a bit more damage earlier and the enemy team has no choice but to build them to, or risk losing lane. So you see both sides with lethality.