For Christ sent me not to baptize, but to preach the gospel: not with wisdom of words, lest the cross of Christ should be made of none effect. 1 Corinthians 1:17

Some believe that baptism is not relevant and that Paul said Christ did not send him to baptize but to preach the gospel, making water baptism not part of the gospel and at best unnecessary.

If Paul was not to baptize, then one would think that Paul had an auxiliary ministry to others because not only Paul preached the gospel — all other apostles who also preached the gospel  baptized. The commission by Jesus to his disciples to preach and baptize was so general that even non apostles baptized, such a Philip the evangelist, and Ananias, a disciple: these were in Christ before Paul. So why did Jesus restrict Paul from baptizing?

Moreover, If the act of baptism was not part of the gospel, how did the eunuch get to ask for his baptism if it was not part of the good news Philip preached to him, and why did  Paul not exclude baptism from his gospel to the Romans (Rom 6:3), Corinthians (1 Cor 12:13), Galatians (Gal 3:27), Ephesians (Eph 4:5) and Colossians (Col 2:12)? And for what else would he have overstepped his boundary as to baptize so many, if not for the gospel’s sake?
Note that baptism is
1. the counsel of God (Lk 7:30)
2. the commandment of Christ(Mt 28:18-19)
3. the doctrine of Christ (Heb 6:1-2)
4. the ordinance of Christ (Act 19:3-5)

Baptism being the counsel of God, those that rejected even John’s baptism, were guilty of rejecting the counsel of God.

Realize that baptism is the commandment of Christ. He that obey not the commandments of Christ  loves not Christ (Jn 14:15,24), is an anathema (1Cor 16:22), and Christ cannot be his saviour (Heb 5:9).

More so, baptism is the doctrine of Christ. He that hath not the doctrine of Christ, hath not God (2Jn 1:9).

Baptism is God’s ordinance. He that resists God’s ordinance, resists God (Rom 13:2).

Now knowing the divine weight of baptism, and implications of rejecting it,  if Paul was sent not to baptize then he was to be an auxiliary apostle who Christ only licensed to preach, but not permitted to baptize. But no that was not the case, Paul baptized many times, and even explained to the Roman Christians that through baptism they were buried with Christ. Preaching that one is buried with Christ through baptism is preaching the gospel of Christ, and the act of baptizing to be buried with Christ can’t be anything other than part of the gospel of Christ, for where the gospel of Christ is not preached, who would talk about being baptized in the name of Christ.

What then did Paul mean since, obviously, he did not mean that baptism was not part of the gospel of Christ?

What Paul meant was that Christ did not send him to raise disciples for himself through baptism, but  sent him on a gospel mission.
Understand that the use of the term baptize in the context of 1Cor 1:17 was for to make disciples as in the case of Jesus making and baptizing more disciples than John (John 4:1). Observe that the division in the church of Corinth was along the lines of “who of the eminent preachers are you his disciple, at least by baptism?” For baptism was also a sign of discipleship. This Apostle Paul  raise his voice against, questioning them if they were baptised in his name, and thanked God that none of them could accuse him of baptizing anyone to himself (i.e baptizing anyone in his name). He refused to claim anyone for his own sheep, noting that Christ did not send him to baptize a group for himself but to be a general preacher of the gospel of Christ to everyone not in wisdom of words lest the gospel be of none effect.