Maybe I wasn't searching correctly, but I was recently discussing healthcare and taxes with someone and briefly searched on the Healthcare.gov exchange to look at prices. There were only three PPO plans (where you can freely go to any doctor in network), and all three were HDHPs, all from the same company. There were many HMO plans, some HDHP and others with low deductibles, but often extremely small local networks and limited choice of both PCPs and specialists.

> This makes health insurance cheaper to the employer than to individuals.

One other thing to note in your analysis is that most large employers are not buying any insurance, but actually self-insuring (funding the claims out of their own pool of money). So the employers are actually acting as insurance companies for their workers, rather than simply buying and reselling commercial insurance.

There would be additional considerations beyond taxes in analyzing whether this type of insurance is more economically optimal, for example, the fact that each company has a distinct risk pool which may not be similar to the general population, depending on the company.