Perhaps the problem with the original question is the title itself, "Sola Scripture." What about studying the scriptures in Christ with Christ directing and instructing? That implies relationship, not "sola." or on our own.
Personally, because of the numerous examples in the scriptures, I believe that there is still true discipleship, but it has little to do with being a follower of man. It has everything to do with being a follower of Christ. "Take up your cross and follow me."
Peter ministered, and also demonstrated the Power of Christ in Him. Paul did as well.
There's a point in the scriptures where Jesus is speaking to the scribes and pharisees where He says:
Matthew 23:15 Woe unto you, scribes and Pharisees, hypocrites! for ye compass sea and land to make one proselyte, and when he is made, ye make him twofold more the child of hell than yourselves.
They were making disciples unto themselves.
Do you think this is still happening (in some cases) today.?
Paul always pointed to Christ. In Ephesians 4, Paul speaks of the body of Christ and expounds on Christ being the head of each individual in the body. Thus, all in Christ will speak the same things. He expounds on there being one Lord, one faith and one baptism and, "one God the Father who is above all and through all and in you all." Then he speaks about the different parts of the body, and the gifts given to each for the edifying of one another for the "perfecting of the saints, until all parts of the body come into the unity of the faith..." It's a clear picture of growing and maturing in Christ as individuals and as a body. Paul also gives examples of the way that is not right, not walking in the vanity of our their own minds because of ignorance, having their understanding darkened, and giving their own-selves up to living a life that is not pleasing to God.
Which I would say, is the true job of a Preacher.
Ephesians 4:20 But ye have not so learned Christ;
Ephesians 4:21 If so be that ye have heard him, and have been taught by him, as the truth is in Jesus:
Ephesians 4:22 That ye put off concerning the former conversation the old man, which is corrupt according to the deceitful lusts;
Ephesians 4:23 And be renewed in the spirit of your mind;
Ephesians 4:24 And that ye put on the new man, which after God is created in righteousness and true holiness.
Discipleship has to do with pointing people to Christ, and seeking, knocking and asking HIM for the true revelation that we can only comprehend when the vail is removed from our eyes through Christ. Just like the two disciples on the road to Emmaus, whom, after Jesus broke the bread and blessed it and disappeared from their sight, said, "Did our hearts not burn within us as He opened up the scriptures to us along the way."
If the veil is removed from the eyes of those in Christ, wouldn't that imply that everyone in Christ would see clearly in the scriptures as they seek it out in and with Christ?
There are so many scriptures throughout the word that point to true discipleship.
Psalms 25:4 Shew me thy ways, O LORD; teach me thy paths.
Psalms 25:8 Good and upright is the LORD: therefore will he teach sinners in the way.
Psalms 25:9 The meek will he guide in judgment: and the meek will he teach his way.
Psalms 25:12 What man is he that feareth the LORD? him shall he teach in the way that he shall choose.
Galatians 1:12 For I neither received it of man, neither was I taught it, but by the revelation of Jesus Christ.
True discipleship is being taught and receiving revelation through Christ.
Jesus Himself confirmed this when He said:
Matthew 7:7 Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you:
Matthew 7:8 For every one that asketh receiveth; and he that seeketh findeth; and to him that knocketh it shall be opened.
And when He said, "...If you continue in My word, you are My disciples indeed, and you shall know the truth and the truth shall make you free."
Humility, coming to Him like a child, (That means, letting HIM answer and not jumping to our own conclusion, but waiting on Jesus.) Seeking answers directly from Him, asking Him questions, and continuing in His word are all parts of being a disciple and making disciples.
Jesus taught the disciples these things, the very things they taught. Even after He ascended into heaven, Jesus was still with them and in them, ministering through them, and those who matured in Christ, went on to do the same, always beginning with the remission of sin through repentance, and belief in Christ Jesus.
Those who joined and were in Christ, were expected to mature and have the same relationship in Christ that the very first disciples had. Jesus taught them.