The poorest kind of argument you could make is pretty much the "It's not like real life" argument. It's not a realistic game and it's not trying to be a realistic game. It's an arcade game and Battlefield has always been an arcade game.
Take the stupid glint away and make sniping hard and realistic like BF3.
Battlefield 3 had scope glint and it's not realistic. The reason it was harder than in Battlefield 6 is because it had unrealistically low bullet velocity, which would produce pretty severe bullet drop at a decently realistic 9.81 m/s² (compared to 15 m/s² on most other guns). In Battlefield 6 you have almost double the velocity of Battlefield 3 (which is quite realistic) and you have a drag co-efficient that simulates air resistance, which slows down bullets over time, though that can be reduced quite a bit by using long-range ammo.
The reason they made snipers ADS quickly, is because they don't want snipers to only play Firestorm and sit on a mountain all day. The average engagement distance, even for snipers is well within the 125 meter range. That's why the sweet spot zones aren't at 200+ meters. If you'd make them ADS slowly, they couldn't ever play the objective because they wouldn't be able to respond in time. If all the maps in the game had 500+ meter sight lines, it'd be a different story.
I don't think snipers need attachments that reduce the drag co-efficient. They don't need the sweet spot mechanic. They don't need the range finder that immediately zeros the perfect range either. They could even tweak the bullet velocities to be closer to 700/800 instead of 1000+. There are plenty of ways to reasonably nerf them, without touching the things that allow them to be useful to the team.