Purely Anecdotally I have to say my experience is the opposite. Depressingly I've met many City fans on my travels, but it's also that type of transient, 'football appreciator' type fan, who also "likes Arsenal and Chelsea".
City are certainly pretty big across Africa (potentially Yaya Toure connection). There were always many Scandinavians in Manchester with City shirts on when I lived there for a bit, presumably Nords after both Haalands represented them. Additionally, kids growing up worldwide today, with no connection to the UK or parental influence, will surely be far more drawn to City than United. They'll be too young to understand or give a shit about this controversy and the shine of Manchester United is wearing off. I suspect Cities' global reach is disproportionately bigger than their share of the UK fan base, hence the low numbers at parades and memes, but many of their current numbers are legitimate(ish).
Additionally numbers are just rising across the board as growth of the Premier League rises each year, swelling the numbers of all, but mostly the top clubs ever further.
