Yes, it is only a theory. Especially that it's not true. There's evidence that gravity exists. Humans (#1) do not have wings, and if a person were to jump off a building, he'd fall, not float or go upwards on his own. That's evidence. And it's proof that gravity exists, as Newton said, gravity is happenstance. Now it is also true that 'laws' such as gravitational forces can be overturned by a force greater than a current gravitational force. And that without going into space. Realizing you probably don't believe that, I see no reason though why that is not true.
The evidence for the theory of evolution is presented without any reality. It's
all based on looks. And some similar genes here and there. And scientific posturing as if to augment the basis of the theory. A branch here and a branch there, conjectured. Molecules here and there. That is NOT true evidence of the theory. If I believed it, I would present the logic as you do or don't. I believed what they taught me in school. Not being a science major, I really didn't question it. Now I do. The questions are multitudinous. And really, as you say, there is no proof.
But if you think it is true, with or without experiments that prove the theory, that's what you and many others think.
It does not make it true.