I was just about to mention that we already have this.
Though, frankly, if all of your income is W2 and you haven't fucked up your W4, you shouldn't have to file at all. If you're a W2 wageslave, the government knows how much you get paid, how much you pay in taxes, and whether you owe extra or have a refund due. Having to file a tax return in situations like that is just bureaucratic bullshit.
The IRS already started rolling out a free tax filing app a couple of years ago.