I've litigated cases like these before. The IRS enforcement reaction is swift and severe.
Penalties for the employer are heavy and rarely waived. It would be rare for a business like this to stay operational long enough to issue a W-2.
A business like this would probably be shut down by the IRS and have the people responsible for the payroll function, at a minimum, promptly burdened with tax liens, within four to six months.
These cases also constitute a significant share of all criminal tax prosecutions. The odds of someone doing this spending several years in federal prison is high.
Generally speaking, if the wrongdoing is fully on the part of the employer without the collusion or knowledge of the employee, the IRS will not force the employee to double pay the taxes that should have been withheld by the employer in this situation. Instead, this IRS will try to recover the amounts that were withheld from the employees but not delivered to the IRS. It will seek to recover these amounts from the employer and also from other responsible persons in the organization (and from outsourced professionals) with the authority to pay the IRS who did not do so. There may be circumstances, if push comes to shove, where the IRS could collect from the employees in a case like this one (I've never had occasion to need to research that issue), but that would be the rare exception and not the rule, in practice.
On the other hand, if the employer simply does not withhold taxes or prepare W-2s at all, and either 1099s people who should have been classified as employees (or files no information tax returns at all), the IRS will generally insist that the employee pay income taxes on the full amount owed and that they pay the employee part of payroll taxes. It will also pursue the employer for the employer's share of payroll taxes. The employer will also be jointly and severally liable for any taxes that should have been reported and subjected to withholding that are not paid by the employee (perhaps because the employee spent all the money). Sometimes cases like this are also criminally prosecuted, but it is less common to do so.