Context
The apostles of Jesus were the eyewitnesses and we are the jurors. Promises made to the apostles in John 13-17 are not made to all of us. The context is about a long discussion Jesus had with His twelve witnesses. Jesus said to them "And you also will bear witness, because you have been with me from the beginning" (John 15:27). We are not the witnesses. We were not with Jesus from the beginning of His ministry.
So, it is not right to take what Jesus said to these witnesses and apply it to yourself. For example, the direct help they would get from the Holy Spirit is not also extended to us. The Spirit was going to be a Helper to the apostles in a special way. He would help them "remember all the things I said to you" (John 14:26). Jesus did not say things to us. He said things to the apostles. The Spirit was not going to help us remember all the things Jesus said to us. He was going to help the apostles recall all the things Jesus said to them. The Spirit was going to help them with miracles (John 14:12) to confirm the testimony, but Jesus is not sending us to be His witnesses with miraculous help and recall of what Jesus said to us from the beginning of His ministry.
The Spirit was going to "guide you [the apostles] into all truth" (John 16:13). The Spirit had not revealed the New Testament documents when Jesus was talking to the twelve apostles. They were going to receive perfect recall and be guided into all truth. The result of their guidance is that we have their truth and testimony confirmed and written down for us as jurors. We are beneficiaries of the Help the Spirit gave the apostles, but we are not guided into perfect recall and we get no direct guidance from the Holy Spirit. Our guidance comes from the New Testament which came to us through the Holy Spirit who guided the apostles and prophets.
It is a mistake to take the promises made to the apostles and pretend that these promises were to everyone. The context tells us that these promises of the Helper were to the apostles. We benefit from the guidance and help the Holy Spirit gave them in that we can trust the testimony preserved in the New Testament. The New Testament is the product of the Help the Holy Spirit gave the apostles. We get to examine their Spirit-guided testimony and draw conviction from the Spirit's words in the Bible. Be careful not to misapply the context of words. Context is important to proper understanding and proper applications. Our guidance from the Spirit comes to us through the scriptures, not a feeling we attribute to the Spirit.
