Tank destroyers are reactive units. They're so common in teamgames because the maps are so lanely and heavy armour is so prevalent.
The actual way to fix it is to replace all the Red Ball Expresses and Alliances of Defiance with wider maps, and to add point-blank penetration spikes to all vehicles so that Tank Destroyers aren't the only answer to heavies.
I doubt such changes would be popular though.
True, lane-y maps are the crux of imbalance. Either the map favors arty, or heavies or both (port of hamburg). And if it's not a 3v3+ poorly designed map then you have 2v2 and 1v1 maps which favor encampments and have great Schwerer positions. Maps need rework.
USF is pretty much designed around blobbing. They don't have any elite infantry. The starting ones are the finishing ones and the current meta build (3 rifles into captain or lieutenant) pretty much seals the deal unless you lose them along the way. It's better to probably send them in pairs but alongside microing AA HT (micro hell), ATs and Pak howits, (+ later easily penetrated medium tanks) it's difficult to pay attention and not get wiped by some bundled nade or rifle nade or stuka or werfer. The large versatility of USF would be a heaven for a CPU, but for a person it's quite hard. USF is for a reason most micro intensive and mobile. You win some, you lose some.
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Also, f*** AA HT: The attack order doesn't work since it will always try to turn around (so the gun will not face it) and the attack ground is even worse since it will just keep spinning in place. With the handbrake I curse the person that decided to design the unit thusly and make it a hotkey-micro-hell.
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