Actually, I would make the case for removing the current blur effect from low scope quality. A large problem snipers in most FPS games face is severe tunnel vision due to the scope/lowered FOV blocking peripheral vision. Since low scope quality lowers your entire FOV, it's already putting you at a disadvantage. The current blur effect unnecessarily exaggerates that disadvantage. Sure, it might be easier to track targets near your scope, but it's harder to find them.
You're completely ignoring the fact that the high-quality scope has a HUGE blindspot between what is seen within the scope and what is seen in the (unzoomed) edges of the screen. Target acquisition when already zoomed is 100x harder than low-quality because of this. In low-quality, if you see people in the (blurry) edges of your vision, you just move them into the scopes view...
Any argument about "lower FOV means I can't see as much" is totally ignoring the fact that, sure the high-quality retains the high FOV... but that's only a sliver of vision on the edges of the screen, followed by that MASSIVE blindspot, and then the scopes view. I'd much rather have NO blindspots to my front, and a narrower cone of vision...than a huge FOV, but a massive blindspot surrounding the area right where I'm looking
not to mention the MUCH lower FPS you have in the high quality.
Low quality is 1000x easier to operate because of all these reasons. Not gonna provide picture examples since that's already been done.