The largely serve people who are self-employed, or work for businesses that don't offer insurance. People in the individual market. Plus Tennessee's Tenncare - a state program uninsurable people can access, that technically is not a risk pool. Florida - currently not open for new enrollment.
Legislation is pending to reopen it.
Now the small group insurance market is facing cost problems in many states. The individual market is growing again, and risk pools are also growing again, though they still represent a very small section of the population. Premiums are up by a similar amount. The increases are not all due to inflation. Partly due to enrollment growth.