As someone who plays to win, I'm usually inclined to play at 100% performance because of how risky and short-lived EFT matches can be, even if it's just a Scav run, because in my mind even dying as Scav is a net loss of both potential gear and time. However I feel like this tryhard mindset comes at a harsh price; Moving at a slow and careful pace leads into this persisting paranoia that you could always at any moment hear a single footstep or a quick rustling in a bush. Worse yet, when I actually do hear something nearby, I end up slowing down even more; "How far is the guy?" "Did he stop moving?" "Does he know where I am?" "Is he aiming at my corner?" "If I focus on him, what if I expose myself to someone else?" Of course there's always the chance that it's a false alarm and I just imagined a footstep when it was actually just my PMC turning too quickly (in a bush), which means I'm wasting time and nerves over nothing. Being at full attention span usually means that I soft-burn out after just a few matches, even if literally nothing happened during them and I got out with full bags and mags.
Lately however I've noticed after wearing the Kolpak helmet (or basically any muffling helmet) that despite running with terrible gear, I play more aggressively and decisively, spending a lot more time boldly sprinting into corners and chokes. This lead me into the idea of just lowering (not muting) my sound to the point that I could basically only hear gunfire and barely audible scav voicelines. I've limited myself to low-mid gear runs while on low-sound so far, however the experience of those matches was truthfully a lot more tolerable than with competitive audio settings. Yes, I admit, it's gotten me killed once or twice, but mostly because I ran into a scav with a shotgun who shot me at point blank into [Head, Eyes] instantly (and that's happened to me before, even with normal sound settings). Those kind of deaths occurred less frequently than I expected though. In fact, even on maps like Factory, where sound plays a big role due to the small map-size and CQC room combat, I find myself taking bolder actions like sprinting up the rafters and just looking for moving targets instead of listening for them, when otherwise I would be terrified to even think of going up there simply because of how much noise I could hear myself make.
There's also the thought stuck in my head where ultimately it doesn't matter much if you go slow or fast around a corner; If you peek a corner slow and carefully, you are guaranteed to be tapped in the head IF there is a guy who might have heard you before you were sneaking. However if you play fast and hard, the guy knows you're coming, but they'll have a much harder time hitting a moving target. With playing slow, the chance of being spotted may be low, but if you are in sights, the chance of death is high. With playing fast, the chance of being spotted will be high, but you are more likely to be able to return fire from a miss.
Not having the stress of constantly filtering incoming audio for important cues just relieves a lot pressure (and nuisance from loud wind ambiance), and I swear that it also unironically improves both spotting and aiming, since there's one less sense to pay attention to, and your nerves are calmer so you don't panic spray on contact or flinch/get jumpscared by a loud bullet.
I don't reckon that many people have deliberately "gimped" themselves this way, however maybe people that wore muffling helmets could pitch in if they noticed a change in personal playstyle and game experience.