Very good but flawed game. According to Sid himself one of last projects he worked on personally, and something he enjoyed and wanted to experiment with for a long time.
Takes a lot of things that made Civ great and streamlined them.
Think Civ 2 but better.
Unfortunately bugs, fanbase mostly on PC (PS1 Civ 1 and 2 weren't that big) and console exclusivity hurt the game. Failed experiment but I am glad it happened.