The people you asked aren’t neutrals though. Also, there aren’t many neutral football people here in England.
Those two points aside, I think it’s varied and personal. My boss is Arsenal season ticket holder and used to hate City but now says he’d support us cos of the relationship we’ve built over the years and I don’t shove our success down his throat, nor their failures, and I was there when we were shit. I wouldn’t mind Arsenal winning it if they were playing Bayern Munich or any team with Ronaldo in it. One of my best friends is a rag but his Dad is blue and so am I, so, bizarrely, he’d prob like us to win if we got there. The feeling isn’t reciprocated in his case, though I would be gracious. Armchair fans of other premier league teams who grew up in the 90’s when football was invented and experience the game through tv/internet probably wouldn’t be cheering us on, especially with us being dirty-oil-money, human rights violating plastic Arabs.
Varied and personal I’d say.