Considering the usual priorities of large companies, it does seem likely that large parts of their savings from health insurance contributions, in this hypothetical situation, would go to shareholders through dividends or share buy-backs, rather than to the employees in the shape of higher salaries. But you know, the same was true for the corporate tax reductions they got from the recent Republican tax cuts, which were supposed to stimulate growth and whatnot. To some extent, they surely did - but a large part of it was sort of wasted in the sense that it benefited shareholders rich enough that the extra profits gained didn't have much impact on their lives.

Whenever you make this kind of large changes, there will be people who directly benefit and people who directly suffer. Sometimes - though I'm not sure if it's the case here - the total benefit is clearly larger than the total loss, but that may still be scant comfort if the winners can't be bothered to share their gains with the losers, and the government doesn't dare to step in and force them to.