I have been reflecting on the unprofitable servant Jesus spoke of in Luke 17 as it relates to other truths Jesus revealed. I find it interesting Jesus would speak of unprofitable servants when in John 15 he says I no longer call you servants but call you friends. So how do these reconcile with each other?

In Luke 17, Jesus is not calling us servants. He is teaching about our attitude. The disciples had just asked him to increase their faith. In response Jesus taught about the faith of a mustard seed and doing great things. That is when he pivots to speaking of unprofitable servants.
Jesus is getting at our attitude by speaking of unprofitable servants in a parable. There have been countless people in the history of the church who Jesus has called to do wonderful things. What should our attitude be when Jesus calls us to do wonderful things?
No matter what we do in serving Jesus and others, we are only able to do so because Jesus empowers us through the Holy Spirit. The attitude Jesus is teaching through this parable is humility.
Our identity in Jesus is that of friend, child of God, royal priesthood and more. Out identity in Jesus is a gift from God not something we have earned just as our salvation is a gift from God not something we have earned which is why Ephesians 2:8-9 says:
For it is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God— not by works, so that no one can boast.
Serving Jesus, following Jesus, is not anything we can boast or brag about. We should give glory and credit to Jesus out of humility and gratitude that he involves us in his work.
Thank you for reading. God Bless.