While there is obviously some risk, in my experience it is very well compensated. If anything, I think an irrational level risk aversion means there are basically not enough good freelancers to go around and the demand/pay is high.
The standard formula I recommend to a new freelancer is (what-you-would-make-as-salary / 50 / 5 / 8 * 2) = hourly rate. Anything less is undercharging. So if you would make 100k in salary, you can’t charge less than $100/hour. This is an absolute floor.
If you follow that formula, you’ll be able to cover the healthcare, tax accountant, gaps between work, and other expenses and still make your base salary.
But the ceiling is much higher. For a company, hiring a full time employee is just too much risk. You have a few hours of interviews to determine if they will be a good match, and if you are wrong, it is an extremely expensive mistake. Likewise if things slow down, you’ll have no flexible capacity. Freelancers are a dream come true.
Also, in my experience, companies do not think of freelancer rates in the same way as salaries. Freelancers are not on the organizational chart as it were. Whereas standard HR hires and the attached salaries come with a load of political and ego driven baggage, freelancers are thought about more like buying a new office printer. If there is a need and the budget, the company will hire you and you might be making 3x what the project lead makes.