My expectation is that the "mass deportations" will quickly morph into "mass incarceration" will quickly morph into an enslaved workforce.
There will probably be one wave of deportations just to "show we mean business" or something and then the news will move onto the next distraction while the remaining undocumented immigrants are quietly sent back off to do the jobs they were doing only now the business don't have to pay them.
We've actually discovered a few of these! Though, nothing quite so catastrophic as you might be thinking.