The plain meaning of 'He' is one person. Similar with 'I'.
Trinitarians seem to accept that referring to God, inclusive of 3 persons, as 'He' is appropriate. The view of Trinitarianism is that God is One, and therefore it makes sense that God deserves a singular pronoun.
But in English we have a singular pronoun that describes something that isn't a person, and that is 'it'. For example, if you have a team with 3 persons, you wouldn't refer to that team as 'he' or 'she' - rather, the team would be referred to as 'it', even though it is made up of persons. Similarly with a family, say.
It seems straightforward that when referring to a person of the Trinity, it makes sense to use 'He' (at least with Jesus and the Father). This is unproblematic.
What is the reasoning given by Trinitarians for using 'He' instead of 'It' to refer to God, inclusive of 3 persons?