I definitely think companies would drop plans for lower-wage, lower-skilled workers, roughly below the income threshold where they would qualify for subsidies. But I don’t think they’d find it advantageous to do so for middle and higher-income people who would have the options to seek employment from a competitor.
They have no choice. If they do it for one group they will do it across the board. Check the Wall Street Journal, they had an article about it today. I've heard the same thing from an executive at a large company. When it starts it will be to late to reverse course, that's why the employer mandate got pushed back.