"Sonic the Hedgehog 2" originally was going to have a time travel system.

The statement is true because Sonic the Hedgehog 2 was indeed originally planned to feature a time travel system. This can be seen in the finished game as well as in early design documents and concept art. The concept of time travel was ultimately introduced in Sonic CD, released in 1993, which allowed players to travel between past, present, and future versions of each level. This feature was likely removed from Sonic the Hedgehog 2 during its development due to time constraints or gameplay considerations.