I too.
It’s a yankee thing, especially since apparently Lincoln recognized it permanantly.
Bear in mind there is not really a strong connection, since there was no continuous thanksgiving in memory of this event. It’s a tenuous relation. Thanksgiving was common because people saw reasons to publicly thank God for good things. It wasn’t just this once.
Yes, I believe that the Spanish also held Thangsgiving services upon landing in St. Augustine. I always say that the Massachusetts folks just had a better PR machine!