I relate to many of your points.... to clarify - here is the definition of "Managed Care" = A term originally used to refer to prepaid health plans (generally, health maintenance organizations [HMOs]) that furnish care through a network of providers under a fixed budget and manage costs
That describes "Medicare Advantage" plans NOT "Original/traditional Medicare.
I fortunately have Original Medicare (Parts A, B and D) and I buy a Medigap policy for the 20% not covered by Medicare. I never see a bill and I can self-refer to any doctor that takes ORIGINAL Medicare, I need no approvals and have no copays. Original Medicare is the best health insurance ever! Before retiring, I had my employer plan and that was definitely inferior to Original Medicare: more expensive, less choice and complicated paperwork for me.
And the kicker? For seniors on Advantage Plans that realize the shortcomings...they can switch back to Original Medicare BUT buying the Medigap/supplemental plan may not be possible as the insurance companies no longer have to accept you or can charge you more. So they are stuck. Do not fall for the advertising on TV about Medicare Advantage plans and all the so called "extras".