As one of the players in such a closed Border Civ, let me try to explain a bit.
In this Case, 5 of my real Life Buddys an me joined a Civ and closed Borders sortly after. It is our 3rd Game as a group. We talk to each other every day via TS. The last times we were stuck in a max Player Civ, which makes you unable to "Win the Game". This is because of a massive unballence in the Game. We went into the Game 1811 BC and went City Siz 8 in a few hours via one Great Person Fertality Rites. a 1 GP Renesance and a 1GP Industrial Revolution later, your City looks acceptable.
In a War, it is a nice effort for anybody to give Troops, but i Lost to many Wars, due to 1-3 Unit Stacks, that prevented 20-40 Unit Stacks to enter the battlefield.
In Max Player Civs i have seen people buying Wonders, within 2 or 3 moves toward losing a battle ... We all try to give hints or talk to people but there wasnt much a response ...
We are 8 people in our Civ, so we are close to your numbers and i cant understand 1-3 People Civs. but i understand the reasoning behind it...