Even if nothing was done on purpose, it’s still cool.
This is the part in question:
Source: reddit.com
Maybe as you just watched that you thought "whoa, did I just see Christopher Reeve?"
Source: reddit.com
Look at the gif again. At the very beginning you can see that the lips and nose are thinner:
Source: reddit.com
Here's the frame that looks most like Reeve:
Source: gif-explode.com