But all else is not equal. And the argument is not that the tax prep companies are out to complicate the tax code, qua liability and subsidy, but that they have frustrated efforts to allow the IRS to offer a simpler filing experience to the public. The usual argument is that if the IRS were to simplify the submission of taxes and offer its own tax prep app, it would be perversely incentivized to maximize its take rather than minimizing taxpayer liability.

Of course, Congress could just pass a law mandating that the IRS take as little as legally required, but as you are surely aware the instant conservative view is that administrative agencies are rapacious out-of-control behemoths restrained only by the heroic efforts of a few valiant champions of liberty etc. etc.