There's a sweet spot for the number of words that should be on a shirt. Some people would say that number is 0. Those people either don't like shirts with words on them, or they are illiterate. Think about it. It's like you're taunting them. The words on a shirt might serve a purpose, like listing tour dates, or it might just be a joke. Very rarely, however, are the words on a shirt essentially a love letter like in this case.
This guy must have custom made this shirt saying thank you to his favorite director, Steven Spielberg. Out of all the shirts to wear on that day, he chose the right one. By the look on both of their faces, it's clear to see that the shirt did its job. I'm guessing this guy hasn't seen Indiana Jones and the Kingdom of the Crystal Skull though.