The NT is all about Jesus so it makes sense that the name Jesus appears so frequently. To some this might be evidence that Jesus in some way replaces Jehovah of the OT, but this is not a very careful reading of the NT text. All the writings of the NT make it abundantly clear that the whole purpose of Jesus’ mission was to glorify God and his name (John 17.26) and that the exaltation of Jesus is ‘to the glory of God the Father’ (Phil 2.11).
When you realise that the name Jesus (then pronounced Yahoshua) means “Yaho saves”, and that the first Christians were very aware of this fact (Matt 1.21, Acts 4.12), then you don’t count the instances of the name Jesus and his God Jehovah in separate tallies. Because every instance of the name Jesus (Yahoshua) is in fact a reminder, to the first Christians, and to us if we read the NT carefully, that Jesus is the saviour that Jehovah sent into he world to save mankind.