In the US, even individuals with type I diabetes are able to get a third
class medical with a waiver. There are a lot of misperceptions and anecdotes
regarding the difficulty of getting a medical.

In the pubs, the AME's who are also pilots are listed, suggesting that AME
pilots may be more sympathetic to helping an individual get a medical. On
the other hand, there are certain conditions that absolutely disqualify
people from flying- and in these cases, it is not the fault of the AME.

It is reasonable to ask an AME (or better yet, look up the medical
requirements on the FAA website) about the medical requirements as well as
any concerns you have regarding your ability to fly. On the other hand, if
you willfully hide a known medical condition that might affect your flying
capabilities, you may also open yourself up to a lot of liability issues
that might affect both your and your family in the case of a claim.

Again, MX is not a pilot, physician, or AME. Make your own judgments about
all of this, but if you want to fly it is always worth making the effort,
which is more than can be said for him.