I see that the focus is on Acts 2:38. However, proper hermeneutics requires that scripture is interpreted through the rest of scripture. What about Titus and 1 Peter? The collection of evidence is expected to provide the proper interpretation.
Tt 3:3–7 But when the goodness and loving kindness of God our Savior appeared, he saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit, 6 whom he poured out on us richly through Jesus Christ our Savior, so that being justified by his grace we might become heirs according to the hope of eternal life.
1 Pe 3:18–21 For Christ also suffered once for sins, the righteous for the unrighteous, that he might bring us to God, being put to death in the flesh but made alive in the spirit, in which he went and proclaimed to the spirits in prison, because they formerly did not obey, when God’s patience waited in the days of Noah, while the ark was being prepared, in which a few, that is, eight persons, were brought safely through water. Baptism, which corresponds to this, now saves you, not as a removal of dirt from the body but as an appeal to God for a good conscience, through the resurrection of Jesus Christ,
Perhaps we should see why the disciples were instructed to baptize people?
Mt 28:19–20 Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you.
Although this verse is the only one in our English bibles that says to baptize in three names, we see through the rest of the N.T. that baptisms were done in only Yeshua's name. (That is a different topic if someone questions this later.)
If baptism in water is not needed, because the baptism has already happened by Yahweh's spirit, why the instruction?
Man can dunk someone in water, but the effect of it is done by God. Note that the quote from Matthew ends with "observe all that I have commanded you." It may open another can of worms, but obedience to the commands of Yeshua is a "work." It is not an Old Covenant one, however. We ignore those commands at our peril.
So, those who think baptism alone saves you are missing the rest of the instruction. It is bad theology to claim that one is already saved without obedience. It is bad hermeneutics to ignore the rest of scripture or pass it off as a writer's ignorance of truth while claiming scripture is "God breathed."
Getting a spinal shiver when you did "the sinner's prayer" does not replace scripture.