I think this is probably the right positioning for anyone's decision on managed database vs. running it yourself, or any cloud managed product for that matter.
If you feel you either don't need the managed offerings and/or can manage it to a point where you're spending less of you or your company's time resources on it, then by all means manage it yourself.
If the managed-ness of the cloud offerings are a high enough value for you, then you will pay for it.
Creating, maintaining, constantly upgrading and improving a managed database product takes a hell of a lot of expensive engineer hours. It's probably a better bet for cloud providers to have relatively fewer high-margin customers on that product than they would if they tried to squeeze margins to compete with "I can provision a VM and install Postgres myself" which is also a product they already offer - just buy the VM.
If you feel you either don't need the managed offerings and/or can manage it to a point where you're spending less of you or your company's time resources on it, then by all means manage it yourself.
If the managed-ness of the cloud offerings are a high enough value for you, then you will pay for it.
Creating, maintaining, constantly upgrading and improving a managed database product takes a hell of a lot of expensive engineer hours. It's probably a better bet for cloud providers to have relatively fewer high-margin customers on that product than they would if they tried to squeeze margins to compete with "I can provision a VM and install Postgres myself" which is also a product they already offer - just buy the VM.