But, you have to pay income tax on the value of the shares at the time when they vest, i.e. become non-restricted. You have zero control over that vesting sched

But, you have to pay income tax on the value of the shares at the time when they vest, i.e. become non-restricted. You have zero control over that vesting schedule, and thus the tax bill, and you likely wouldn't have a liquid market for the shares before an IPO. Any gain post-vest can indeed be long-term cap gains, if you hold the shares > 1 year.