I think it could be the last 1/2 ie
start at 1750 (industrialization in first column of techs/civics)
50 turns at 3 years per turn (1900) electrification in second column
25 turns at 2 years per turn (1950)
ideologies/combustion in 3rd column
nukes in 4th column
up to 125 turns at 1 year per turn (2075)
space race/computers columns 5-8
So if they expect you to win in 125-175 turns, the game ends between 2000-2050 (before you get to the final techs unless you are beelining space racing)
first 50 turns is the scramble (imperalizing all the weak civs/IPs)
but ideologies and nukes destroy that, and you shift to “liberating” them to be your allies aka corporate/military outposts
(cold war, etc….some civs get squashed but recover to strength ie irl Mughals, Qing…some get squashed but recover to low significance ie irl Buganda)