I agree that too many of them won't take insurance at all. A number of the insurance policies will reimburse you to a point.
I think I need to clarify. Medicare has taken down the ban on trans health coverage. ACA has not made trans health care have to be covered. If a plan includes trans health care and the doctor has agreed to take that insurance plan, they cannot refuse to cover it. That is a big if. ACA plans may cover SRS, but don't have to except in the states where laws were made to force them to cover it. Medicare, on the other hand, is no longer allowed to simply say no to coverage. Doctors won't deal with Medicare due to the small payment they receive. ACA plans already have a network of doctors who take the insurance.
I know it may be hard to understand the difference, but it is huge.
Obviously, not all doctors have an agreement with all insurance policies. You have to first find an insurance that will cover it, then go through the list of providers to find a doctor that you can use. In at least some cases, if a doctor isn't within the network that covers the procedure needed, the insurance will have to pay in network costs to an out of network provider.
It is still a lot of work on your own to find the right insurance and then a doctor that you can work with.