In a depressed economy many employees will not have a choice of they want to keep their job.
Whether you have Obamacare or not, how is that different. An employer says: "Fuck it, I don't want to spend any money on employee healthcare. I am dropping the healthcare plan effective July 1st!" Sure employees could try to complain but, as you so aptly put it, "in a depressed economy many employees will not have a choice of they want to keep their job."
I don't buy this notion that employers will magically drop healthcare plans. The simple fact of the matter is that when people are looking for jobs, they examine their options and rate them based on criteria important to them. If good healthcare options are important, then employers will have to provide those options to lure the best people to come work for them, whether Obamacare is an option or not.
The calculus that businesses engage in isn't just "Oh, I can pay this fine and save this much over the healthcare plan I have now." That's a
part of the equation, to be sure. But the remaining part, that is just as important is the part that says: "my current employees say that the plan I have them on, which has perks X, Y and Z was a big factor in their decision to work for me and maybe dropping this plan would make keeping existing talent and recruiting new one more difficult."