Literally has the same headshot potential as the sniper rifles, ...
Wrong. Ain't the same - lower.
Before you'd start explaining things to me, please, note this crit is how much i routinely get outta River's overture, by a _netrunner_ build (not gunslinger) - Reflexes 8, Body 3, gear / 'ware largely not for gun damage:
... this thing can be silenced while the snipers can't.
...
Wrong again. There is at least one silenced sniper rifle, and boy, does it deliver.
...
No other weapon allows you to sit or roam and kill with impunity and never get spotted and take targets out in a single second. ...
Wrong, 3rd time. Other weapons can do it too. Namely, properly developed assault rifle build will allow it also - yes, it won't be some 1+ million damage headshots like with overture, it'd be some ~200k headshots, but still massive overkill. Single-shot assault rifles can take silencers, and the obvious benefit is that you get that same weapon able to dish out full-auto whenever the game puts you to any ambush (like when rescuing Goro if to jump back to upper floor ASAP, etc). SMGs too, as well as other pistols and revolvers - pretty much anything which has or can get a silencer.
Quickhacks are not that fast and do not hit as hard, even sometimes leave some HP left even at the same skill and perk lvls.
Wrong 4th time. My netrunner build now dishes some 30k...50k instant hits to up to 3 enemies within 6m radius with electrocute, and up to 7 ~10k instant hits in times wider radius with the poisoning hack. Those are literally instant to anything suffering daemons uploaded, and take out anything in any given room / area without alerting any distant enemies, unless it's some especially tough psycho / boss. Plus, with a single Ping, they work through multiple walls / obstacles. With quickhack cooldowns being nearly zero, and usual quickhack costs being 1, even largest gangs (~20 people) do not survive to the end of a single Ping. Overall, netrunner build is massively better at general stealth, with only infrequent special enemies getting dropped by gunfire instead.
So yeah. 4 outta 4. It's no shame in being mistaken as we all human, but you sorta overdid it a bit.