Thread:Elledy92/@comment-26838855-20190425183005/@comment-26838855-20190429123654

It's not arbitrary though since this film explains that in removing an Infinity Stone you cause a branch in the timeline, not if you just pop back to some point in time. By the rules of the film, Clint and Steve didn't cause any branches.

They also promised to make sure there were no alternate realities made by their jumps - the ones that were, they closed off by returning the Stones. You can't return anything with Clint or Steve to close off that timeline, yet they made sure no alternate realities were created, so those can't have been alternate realities.