Myelomalacia isn't a very specific term. It simply means that the cord is affected. It can be due to different causes such as injuries and aging. The cause of your problems is spondylosis (degeneration) and curvature problems.
I don't know all the particulars of your neuro exams but you certainly have signs and symptoms that suggest cord involvement. The most likely cause is the cervical spine. The combination of curves, bones spurs and degenerated cartilage is obstructing the contents of the spinal canal in the lower neck. The bones spurs and disc are definitely compressing the vertebral veins. Compression of the vertebral veins puts back pressure against arterial circulation and oxygen flow to the cord, but I doubt that it is completely cutting off supply. Nonetheless, over time, chronic decreased arterial flow to the cord can do permanent damage. I discuss it all in my book. The three villians are chornic edema, ischemia and decreased CSF flow. Your neck is most likely affecting all three to one degree or another.
Removing the spurs and protruding discs can only improve arterial and venous flow through the area, as well as CSF flow which would be beneficial to the cord. How much you regain in strength and improve in symptoms depends on the extent of damage. Unfortunately, regardless of whether they do open or endoscopic surgery there is no way to determine the outcome before hand and surgeons claim to have less success with cord compression, called myelopathy. As far as I am concerned, unless it can't be done, it would be far less risky and much better for you to have endoscopic surgery. It will cause far fewer problems.
Do you have a neuro report on the strength of your legs, feet; arms, hands and fingers; muscle reflexes; sensation; pathological signs such as: hyperreflexia or areflexia, Babinski, Hoffman, Lehermitte etc.