Based on the data from overbuff, both snipers have a low win rate, and Widowmaker specifically has a low pick rate as well. Nerfs on sniper heroes would make them unplayable in the game.
It is important to note that nerfing a hero solely based on community demands is not a viable solution. Overwatch is not solely an FPS game, but the FPS element undeniably plays a significant role. Players are expected to learn how to effectively deal with snipers by utilizing cover, flanking, and diving techniques. These strategies are integral parts of the game and often contribute to the enjoyable aspects of gameplay.
(You can check my profile.) In competitive mode, I play flex support and tracer a lot. Widowmaker is a counter against flex support and hanzo is a counter against tracer. I never complain about the one-shot kill even there are some lucky shots because taking better position and timing, staying sharp is one of the most thrill thing in the game.
Only toxic players tend to attribute their deaths to the faults of their teammates and unbalanced snipers (which is not true as stated in the 1st paragraph). If game developers were to solely follow the opinions of these crying babies, it would result in a worsened in-game experience and the game would be dead soon.
Many ppl have discussed how ridiculous the distance for widow is. I will give you an example to show you why hanzo cannot one-shot kill 250hp hero is unreasonable.
Mei’s alt fire is projectile, similar to hanzo. However, hanzo arrow’s max speed is 110 m/s and Mei’s is 115m/s. If they got headshots, they both need 2 shot to kill the other. As a sniper, headshot does not give you any advantage in a duel.