What do you mean? It's already possible in countries that use the push-tax-bill system. If you're a small business, you self-report. It will be literally the same situation for any small business under a push or pull system - they either choose to self-report or not self-report. No government surveillance required.

The whole point of the push system is to make it easier for anyone who has a simple tax setup. That is, they work for an employer who is continuously reporting on pay checks to the IRS and state revenue departments.