A day over a hundred years in the past that has no modern relevance. This is just the pigeonhole principle in action. If we avoided doing anything on a day where a villainous person did something vaguely of note, there would be no days left to do anything.
It's just math. There are only 366 possible days in a year. You're going to wind up with plenty of coincidences according to the pigeonhole principle. George Takei and Mike the headless chicken are both April 20 births. If they had passed this bill in a few days on the birth of Karl Marx (May 5), would that have been an endorsement of communism? No. The US Congress has business to do, and it isn't going to halt everything because Hitler got born. Let the neo-Nazis care about Hitler's birthday.