You misunderstood one important thing: Dr. Strange did not travel through time. He just looked into 14mio14mil different possible futures to see the one scenario where they could win. His body stayed in the present all the time, as you can clearly see during this whole scene.
And even if he would have been able to really travel there: this future would not be possible if he left, as e.g. Thanos getting the Time Stone was one important thing in the plan...