There's a big difference between countering infantry and consistently 1 shotting squads with no way to predict or react... from 60 range... and behind buildings/shot blockers.
Less sarcasm please. Us adults are trying to have a legitimate balance/game design discussion here.
I'm no pro, but I think that your first thought to avoid a squad wipe from a HARD COUNTER to infantry would be to retreat your squad(s) away and bring them back with something that COUNTERS the Scott. It's not like this thing doesn't show up on your map or even in the fog of war once its fired. I don't run riflemen and paratroopers into a sturmtiger, I retreat them. Hell, I don't typically run infantry into a vehicle designed to kill them effectively(ex: aa halftracks/luchs etc.)
This vehicle isn't that OP, is it powerful, yes, but it's powerful against exactly what it was designed for, uber-vetted axis infantry.
I'll save you the trouble of looking up my player-card and criticizing me for only playing USF like you did the other poster here. Some of us like one faction the best and don't like the others for feeling(or assuming from experience playing against them) that they are far easier to play with. I'm sure my explanation still "boggles your mind" but hey, it's a video game and who cares who people choose to play the game with.