This is an oversimplifying of things IMHO:
A high scoring game just means you can keep the computer barely alive while you spam wonders/cities everywhere until the late turns.
1) The "one city challenge game" is an example of large scores without spamming cities cuz you are not allowed more than one. It started being popular to limit yourself to one city on the honor system (it was not a toggle option then) back in Civ II I believe.
2) My style, tho I try to be adaptive, is usually not more than a few cities. My wide growth then comes from conquest, IF

I even go for that. And I am no stranger to large scores.
Your statement:
A fast win requires more finesse and knowledge of the game.
is also just an opinion which I respect as being different than mine.
Tho I can understand why you say it based on many players style. It simply isn't
really true all styles considered.
I will agree that to be among the best in ANY particular style of play requires more finesse and knowledge of the game...
So yeah, a better than average player should be able win a fast one or a high score one. Each shines best on different days!
And no one, myself included likes the experience of going for a longer curve development game strategy (tall or wide) only to get dealt a decisive blow just at the last possible time one could be dealt by a shorter curve strategy opponent.