Precisely and while yes, each faith has traditions, teachings and beliefs that are distinct and make each religion and it's culture distinct, all three do infact worship the same Deity. Infact if you were to drastically simplfy things it could read like this:
Judaism = Judaism.
Christianity = Judaism + Jesus.
Islam = Judaism +Jesus +Muhammad.
While, yes, Christianity is drastically different from Judaism they still share similar core teachings and Christianity's teachings are based upon the teachings of the prophets of Judaism plus the teaching of Jesus and his disciples and for Muslims, they believe in the teachings of Jesus plus the teachings of Muhammad and his sucessors (whomever one believes them to be) and again, shares core teachings with both Judaism and Christianity. Again, while distinct teachings and beliefs and practices may seperate us, we still worship the same G-d. It again seems silly to me to argue over semantics or words and so on when the answer is clear. Literally, regardless of sectarian arguments, the Deity is the same, the one G-d. I mean, all three are monotheistic and teach that there is only one G-d and that this G-d is the creator of all and that he was the G-d of Abraham and of Moses and of David, if all three talk about this one G-d, who created everything, who is one and that this unity and singularity is like none on Earth,
who do you think this one G-d is? Who do you think they are all talking about? Logic would say the same G-d especially considering all three share the same spiritual father, Abraham.