I said "Laptop" GTX 950, not a SC Desktop version. and mobile phones aren't actively cooled, so operating temperatures limit sustained performance. The shield being actively cooled and mains powered is in a completely different league, like a laptop GTX 950 would.
Just because the tegraX1 is 8years old has no bearing on its technical comparison to low power, cutdown, passively cooled smartphone chipsets. TegraX1 is still maxwell desktop silicon running in a shield, not super low power settings of Switch maxwell desktop silicon.
Your iPhone maybe does blow it out the water, but then without knowing the model, we won't know if it is actually doing full precision floating calculations to match TegraX1 exactly for workloads, many smartphones still cheat with lower precision integer based calculations in graphics, as was the reasoning for an Opengl ES to begin with back in the day, but the need for the Switch to surpass and port the AMD GPU solutions for the WiiU, means it isn't cheating when it comes to zbuffering, etc.