I don't think their first priority is Schedule C filers.  As the report states:

More than 4.2 million partnership returns were filed in calendar year 2018, which is more than double the number of corporate returns filed the same year; however, the IRS audited only 140 of these returns.

Edited to add: Similarly, just 397 of the 4.8 million S-corporation returns were audited.

With enough money IRS could come up with algorithms that have a high likelihood of identifying unreported income.  I have misgivings about this proposal also, but what are the alternatives?  Require taxpayers to self-report annual deposits?