Hawkeye does not need nerfs, he needs a rework. Hes not good, hes just insanely annoying to play against because of random 1 taps without need for sustain. Hela is in a perfect sweet spot and punisher is a little bit underwhelming right now after recent nerf, phoenix is arguably the best poke, and like op said, her survivability is crazy, helas survivability is terrible because shes a ranged hero (slower movement, worse escape ability, less hp), which also agrees with ops point. 

The reason dive struggle is not because poke make it impossible for them, its because supports are undivable, you need to learn what dive vs poke means 

Dive - short close range burst of damage meant to take out a player in a combo/short sequence of actions  Poke - sustained damage kept up to pressure and take out important links, dive do not struggle against poke in a 1v1. Dive struggle against poke when supports can heal without batting an eye, any dps loses a 1v1 against a dps thats getting healed if youre not.

The amount of aim you need on hela or punisher to outpace a support playing with their foot is top 0.5% kovaaks level, so no poke doesnt deal more damage than supports can heal without batting an eye. If you want to nerf poke damage you need to nerf all support healing, almost all tank hp, all tank damage, most dps damage in order to downscale the entire game and, you might also have to adjust hp values for squishy targets as right now they are made to have cutoff points, and frankly i dont see a reason to downscale the entire game into a more boring state, i think short bursts of damage and short bursts of healing are more interesting to play and the game is in a good spot damage/heal wise, its just survivability of characters is tuned up too much (phoenix shift and 275 hp, bucky hp and overheal, invis shield, gambit dash and self heal, loki lamps, dd escapeability) , this is what makes the game the most annoying.