I am not sure why you are obfuscating the issue. Perhaps lack of knowledge.
The Muslim Personal Law (Shariat) Act is a British colonial era law that codified Muslim practices where it relates to marriage and inheritance. It applies to most states in India, except for some (like Goa, Lakhshwadeep, J&K etc; Kerala has a variant of the Act; and so on)
When it comes to similar practices related to marriage and inheritance, other religions and tribes in India have similar legal codifications, such as the Christian Marriage Act (I know Kerala has a variation of this) and the Hindu Undivided Family Act.
Can all these laws be codified under a single civil code? Perhaps yes, but highly unlikely, for a variety of reasons, that is perhaps beyond the scope of this post.
So when you cite the Muslim Personal Law as contemptuous and single out the Muslims for the same, I feel that it is based on the religion of these people that bothers you, and not the differing law itself. Because, if you had studied the law, and studied the similar legal provisions for other religions and tribes in India, your resentment would be tempered.