It's definitely unfriendly to employees, but is rampant across companies. Gusto, for example, has a clause in their bylaws which blocks employees from selling shares.[1]

Want to buy a house or pay down debt? Not up to you. They keep it secret because candidates would absolutely push back if they knew their options were worthless unless/until the company IPOs.

[1]: https://medium.com/@octopoedi/dear-gusto-mission-is-more-tha...