Why is Gnar allowed to have such GARGANTUAN HP regen growth
Forcing a trade on Gnar is absurdly difficult for a melee in the first place, and even if you do his base damages are BS enough that you are far from guaranteed to win such a trade.
Not only that, but after a few levels trading him becomes completely pointless because he will regen tons of health (due to Rage gene AND his massive HP5) while denying your lifesteal with his poke.
It's crazy. At 1.75 growth, Gnar nearly DOUBLES growth of the next champion, which is Braum at precisely 1.0. By level 18, his HP regen is 25% greater than the next champion, which is a juggernaut, Darius.
Like WTF Rito. Just allow this guy to lose lane once in a blue moon.
Edit. And if you think that HP regen doesn't matter, it does. All health regen items scale directly with base HP5, most of them quite nicely like 100%. A Gnar with SV will regen more than a bar of HP in-between waves more than a Darius with SV would. Really, WTF, not every champion is Darius, and Gnar has ANOTHER source of regen.

Learn to play a
counter and stop crying. If
into
, rinse and repeat that combo. flash to hit the stun and kill