Actually I did think of Makarova as unmusical. To me being musical is responding musically, being inside the music and phrasing within the framework. It is not IMO musical to slow down or speed up music to suit your technical limitations or how high you wish your leg to go.
Based on what you are saying, then you would consider Margot Fonteyn's rose adagio as being unmusical because she did slow down the music, particularly to allow her to balance with her arms over her head in attitude. Then among current ballerinas, Ulyana Lopatkina, primarily due to her size, dances slower than other Mariinsky ballerinas, so due to what you would describe as her technical limitations, brought on by her height, she is unmusical.
This thread is titled "Skorik" and I will bring up one ballet role, where what you say, would apply precisely to her. Kitri is a role full of life and energy, all technical limitations with Skorik. so when she danced Kitri, she danced it much slower than normal and I am talking about allegro work, not adagio work. Her being unmusical at all times, made her Kitri even worse.
However, the role of Kitri is in my opinion,a perfect example of allegro work, that can be danced at different speeds and still be musical, within limitations, such as with Skorik, who is totally out of character in energy, interpretation and speed. However, I will discuss the act 1 variation which Maya Plisetskaya made famous with her back leg kick to the head. This is a fast variation and is often danced at varying speeds, particularly which country and ballet company is performing. In Russia, it is always fast, but some dancers have exceptional speed and dance it super fast. I think that the normal fast dancer is as musical as the super fast dancer. The final act grand pas de deux Kitri variation is a similar situation, where even the choreography is not always the same and the use of the fan is often present or non-existent. However, a tiny dancer by the name of Malika Sabirova, 1969 Moscow Competition gold medalist, had phenomenal speed in her variation and in my opinion, her speed did not alter her musicality. However, there are some dancers that try to emphasize their balancing ability and that drastically alters the speed and in my opinion, i am used to this variation, not emphasizing balancing ability and I would consider the balancing variation as unmusical, but some will disagree.