I am in WA state. My family is low income and when we applied for ACA way back when we were automatically bumped to medicaid (for both children and adults). We have been on Medicaid since, in two different cities, and the care has been excellent -- better than anything I had on employer insurance back in the day.
Just like any insurance, it comes down to choosing the right providers. In WA state, at least, we have always had plenty of choices of whom to see. We have never been discriminated against. I'd go so far as to say the opposite. Medical providers know they will get paid as long as their service is on the list without quibbling with a private insurance company. Our GP is excellent, we've had two wonderful pediatricians, mental and physical therapy, and even an ambulance ride and couple of emergency room visits and the quality of care was always excellent. Dental care was great. In fact, my adult son ages out of children's Medicaid in a few weeks when he turns 21. In May it was discovered that he needed a major dental surgery (wisdom tooth growing into his sinus cavity). After it was determined that he won't qualify for adult Medicaid and his workplace benefits don't begin until he graduates and goes on fulltime contract in January, the dental surgeon moved things around so that the surgeries (yep, two) and after care visits would all fall within the Medicaid coverage period.