All employees can also enjoy profits, by becoming owners of a company, either through stocks or starting their own business.
The other obvious risk is that of unexpectedly losing your job. By and large, employees are not financially independent and are at the mercy of their employers. Ownership has the intel and leverage to plan a graceful fall for themselves. Employees are typically terminated with zero notice, while it's a faux pas for an employee to do the same.
Another risk is that an employee will find real conflict with an employer, and stare down the barrel of a well-funded legal team. People have had their lives destroyed by it.
I could see equity being a great motivator if it was less of a lottery. I’m happy to do good work for good compensation and that often includes stock. But I’ve never considered myself “motivated as if an owner” of my employer.