I work in insurance in the department that deals with calculating premiums based on mortality rates. Whenever I see people mention how insurance companies are not accepting people for pre-existing conditions, or not the full cover of claims, I think they need to understand that if insurance companies start accepting all claims then it will inevitably lead to higher premiums as well, which is also something people will complain about then. You can't a system where insurance companies accept all claims, especially those with pre-conditions, and keep a stable premium.
That being said, I'm also not comfortable with companies maximizing profit off the health of people, it doesn't seem morally right to me. A basic level of healthcare should be the right of everyone, so no person should be worried about paying bills for a medically necessary procedure. This should be provided by the government. If someone wants more features on their healthcare plan, then they can go private, whereby I'm fine with companies trying to make a profit because then it's not on the poorest of people and not on basic healthcare.