And that's where your government wonk might say "mmm, why not? We'll take the $21,000, and give $10,000 to the employees in some form of a government-run plan, and have $11,000 left over!"
I'm not saying I'm in favor of it (it would probably cost $30,000 in waste to give the employees the $10,000) but if it really costs $21,000 in taxes to get $10,000 to the employees, as a taxpayer, I have to question whether it is worth it.
Good point and it hasn't escaped me that this may be a government ploy to get that $21,000.
Cross-testing and safe-harbor match 401(k) plans have yielded plan designs that are so abusive (providing the possibility that some rank-and-file employees get either 3%-of-pay annual contribuitons subject to vesting or nothing, respectively) that even government bureaucrats pick up on it. Combine that with the faulty reasoning underlying cross-testing and you have an easy target.