Most companies that do meet the criteria just pay out the employees in lieu of the notice

They just see it as the cost of doing layoffs.

This notice is called the WARN Act.

The pay out isn't in lieu of the notice. What they do is lay off employees on the same day they publish the notice, and just keep the laid off employees on the payroll for 60 or 90 days, depending on jurisdiction (New York requires 90 days whereas most other states only require 60 days). This complies legally, but it's questionable ethically given the whole point of the act is to give employees advance notice of layoffs.

What's funny is watching tech companies try to apply this US-centric approach in other countries. Some European countries have a layoff process that takes multiple months to complete, and requires the employer to have just cause. They can't lay off people just because they want to. Some big tech companies that wanted to lay off employees in European offices failed to do so because of the strong protection of workers.