Humana’s Medicare Advantage product is a Medicare HMO or Medicare Managed Care plan and I would presume you are trying to compare it to Medicare Supplement policies. In general terms, most doctors aren’t thrilled with Medicare regardless if it is traditional Medicare or the new Medicare Advantage products sold by insurance carriers such as Humana or United Healthcare due to the reimbursement (payment) levels set by the government. You provide no specifics so it is impossible to give you a definitive answer. Medicare Advantage products have to cover everything Medicare covers and generally offer an even broader range of benefits to their members. However, the trade off from the consumer’s perspective with Medicare Advantage plans is that you must stay within their network of health care providers for your care to be covered. From the health care provider’s perspective they are almost certainly presented with a different payment methodology under a Medicare Advantage plan than the fee-for-service approach they have been used to and they will find their practice of medicine under greater scrutiny for the quality and effectiveness of the care they deliver. In my experience these types of physician remarks usually boil down to manner of payment and control issues.
You should find a licensed health insurance agent who sells both Medicare supplements and Medicare Advantage plans who can explain the specifics of what each approach does and present each one’s advantages and disadvantages. Your doctor could be giving you good advice for your particular area or they could be expressing their own prejudices.