2000 goals is indeed insane...
It's not that hard to create a 1200-1500 goals player though. Just need to build the team accordingly, so only this star player, and manipulate the draws. I would almost think we had a different engine back then. Very rarely I see 100+ goals season from a player today. A player with 2000 goals must average almost 120 goals per season, while playing his 18 seasons (18-35 years old)...