The Holy Spirit is never wrong, but humans often are, and even those who make a specialty of claiming the imprimatur of the Holy Spirit. The Pharisees could not contemplate the possibility they were wrong. After all, they sat in the seat of Moses, and Moses had a hot line direct to God. So what could possibly go wrong? Other than becoming so deeply committed to their own sense connectedness to God they totally blew it when Jesus worked wonders among them to show, by the Holy Spirit, He was the Son of God. They mistook him for a devil, not because they had any real evidence of malicious motive, but solely because he dared question their pedigree of divinity.
And that act right there is the only place in Scripture where the unforgivable sin of blasphemy against the Holy Spirit is exampled for us in concrete form. They showed they would rather deny the witness of the Holy Spirit acting in power before their very eyes, than surrender their pretense to divine authority. Based on that example, it is much safer spiritually to question the divinity of a human hierarchy, like Jesus did, than to defend said hierarchy by attacking the spirituality of honest critics, like the Pharisees did.
We can all sin against the Holy Spirit!
Do you deny the Mass?
Do you deny the Father, Son and Holy Spirit?
Do you bless yourself with Holy Water every time you step through the narthex of your church? Or is the Holy Water absent?
Do you deny that Mary is the Mother of Jesus Christ, true God and true man?