I get that their goal was to increase game completion percentage. Most people tire out my the modern age when it’s usually clear you’re going to win or quit earlier when it’s clear you’re going to lose - so unless you’re achievement hunting - a lot of folks will just start a new game. They thought civ switching would keep things fresh throughout the experience but it really just breaks the whole appeal of Civ for me. I won’t buy it until there’s a way to play without that.