There is a reason for the nitpicking. Scientists often claim evolution is as settled as the theory of gravity in public forums. You yourself mentioned 2 as what they are referring to when they make this claim.
Is is too much to expect from a well established theory that it be well defined and make testable claims? Put yourself in the shoes of. Non-specialist who is told “evolution is as true as gravity” and think about it.
I am just pointing out that it might be useful for an honest communication to stop talking about evolution as one theory, but rather many competing theories regarding how “modified descendants” emerge and new species are formed.
Instead , what we get is authoritarian assertions that evolution is true followed by just so stories/artistic renderings of what is supposed to have happened.