Same here - I regard Tall as 8-12, really surprised at the number of people who have tiny empires. I get it's easier to manage each one but don't you struggle to get anything done??
Sometimes you don't have a choice.
Had a recent deity game where I was quickly locked in by Khmer and France on both side, and my starting location being really awkward on a narrow strip of land wedged between mountains and coast/lakes.
Could settle a maximum of 3 cities, but even city number 2 and 3 were about to be lost through loyalty by before I had researched craftsmanship (meaning no Governor for quite a while).
My only choice was to rush down France at that point, and the second she got her walls up it was another 5 turns till my cities would have been lost.
That was a reroll for me.
Other cases are perhaps not as extreme as that one, but a recent science victory I pulled off (also deity) had me pinched between several civs and the ocean to the south.
I managed to pull off a successful rush against Persia (go Gaul!), but had to be content with 8-9 cities for the rest of the game after that.
8-9 cities is about the point where I find that I can still manage to win comfortably on deity, and lots of games are like this for me before all the land is grabbed.
I do get some games where I get an enormous amount of land to settle (15+ cities), but that's hit or miss.
Otherwise related to this topic, I do suspect that the answers here will largely depend on the settings the game is played on.
Difficulty being one of them, but also if one plays with fewer players than the intended map size etc.
Games where I can settle 20+ cities are usually extremely rare for me.
Science, religion, and diplomacy wins are quite feasible with a single city.
Does require a lot of cheesing (and cooking) though, at least if we're talking higher difficulties.
One does not start a completely random map and proceed to comfortably win a SV on a OCC.