The holy spirit since Jesus ascended?

The below two (of numerous) passages are understood by most to be the Holy Spirit coming to guide us after Jesus ascends. John 16:7 >Nevertheless, I tell you the truth: it is to your advantage that I **go away,** for if I do not go away, the Helper will not come to you. But if I go, I will send him to you. John 16:12-13 >**12** I still have many things to say to you, but you cannot bear them now. **13** When the **Spirit of truth comes,** he will guide you into all the truth, for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come. 1) Has the Holy Spirit come yet & where is the evidence? 2) Why did Jesus need to leave before the Holy Spirit comes, noting that the Holy Spirit was here since the beginning and throughout?