Neil was brought on to rescue Sunderland’s season in February following a poor run of results and a heavy defeat to Bolton Wanderers, which ended Lee Johnson’s time as manager at the club.
The 41-year-old led Sunderland to the playoff spots and finally got them promoted back to the Championship at the end of last season.
Speakman stressed that following close consideration and what the club felt they needed to get promoted, Neil was identified as the perfect man to take charge of Sunderland.
He believes that the manager would not have agreed to drop down to League One for any other club and conceded that had they not got promoted, Neil would have likely left for a club in the Championship.
Speakman told The Athletic: “We were fixed on the fact that an upturn in our points-per-game ratio was our best way of navigating the play-offs. Alex was the best fit.
“He understood our head-coach model and how it was operating.
“Alex is a very aspirational coach and I don’t think he would have gone to League One for any other club.
“Had we stayed in League One, there’d be a question over whether he would have wanted to continue at that level.
“He’s a Championship coach, at a minimum.”
Sunderland will open their Championship campaign on Sunday when they host Coventry at the Stadium of Light.